Wzw (wirusowe zapalenie wątroby) – Etiologia i przyczyny

Wzw (wirusowe zapalenie wątroby)
Etiologia i przyczyny

Wirusowe zapalenie wątroby (WZW) to stan zapalny hepatocytów wywołany głównie przez pięć wirusów hepatotropowych: HAV, HBV, HCV, HDV i HEV, z których każdy charakteryzuje się odmiennym mechanizmem transmisji i przebiegiem klinicznym. HAV przenosi się drogą fekalno-oralną i jest najczęstszą przyczyną ostrego WZW, natomiast HBV (wirus DNA z rodziny Hepadnaviridae) i HCV (wirus RNA z rodziny Flaviviridae) dominują w etiologii przewlekłych zakażeń, z ryzykiem rozwoju marskości i raka wątrobowokomórkowego. Ryzyko przewlekłego zakażenia HBV wynosi 5-10% u dorosłych, ale przekracza 90% u noworodków, a przewlekłe zakażenie HCV rozwija się u 50-60% pacjentów. HDV wymaga współistnienia HBV do replikacji, a HEV przenosi się głównie drogą fekalno-oralną i rzadko powoduje przewlekłe zapalenie. Dodatkowo, inne wirusy niehepatotropowe (CMV, EBV, HSV, VZV) mogą sporadycznie wywoływać zapalenie wątroby u osób z obniżoną odpornością.

Etiologia WZW (wirusowego zapalenia wątroby)

Przyczyny wirusowe WZW
Wirusowe zapalenie wątroby typu A
Wirusowe zapalenie wątroby typu B
Wirusowe zapalenie wątroby typu C
Wirusowe zapalenie wątroby typu D
Wirusowe zapalenie wątroby typu E
Inne wirusy powodujące WZW

Nieinfekcyjne przyczyny WZW

Alkoholowe zapalenie wątroby
Niealkoholowa stłuszczeniowa choroba wątroby
Toksyczne zapalenie wątroby
Autoimmunologiczne zapalenie wątroby
Genetyczne przyczyny WZW
Inne przyczyny WZW

Następstwa zapalenia wątroby
Czynniki ryzyka WZW
Podsumowanie przyczyn WZW

Kolejne rozdziały

Etiologia WZW (wirusowego zapalenia wątroby)

Wirusowe zapalenie wątroby (WZW) to schorzenie charakteryzujące się stanem zapalnym komórek wątrobowych. WZW może być wywołane przez różne czynniki, przy czym najczęstszą przyczyną są infekcje wirusowe. Jednak zapalenie wątroby może być również spowodowane przez choroby wpływające na wątrobę lub ekspozycję na toksyny, takie jak chemikalia, alkohol czy leki.¹²

Przyczyny wirusowe WZW

Większość przypadków wirusowego zapalenia wątroby jest spowodowana przez pięć głównych wirusów hepatotropowych: A, B, C, D i E. Nie jest jasne, czy wirus zapalenia wątroby G (HGV) jest chorobotwórczy dla ludzi. Inne, rzadsze przyczyny wirusowego zapalenia wątroby to cytomegalowirus (CMV), wirus Epsteina-Barr (EBV), wirus opryszczki pospolitej (HSV) i wirus ospy wietrznej i półpaśca (VZV). Są to wirusy niehepatotropowe, które zwykle nie atakują głównie wątroby i rzadko powodują zapalenie wątroby u osób z prawidłową odpornością.¹²

W Stanach Zjednoczonych WZW typu A, B i C są odpowiedzialne za ponad 90% przypadków ostrego wirusowego zapalenia wątroby, przy czym WZW typu A i B są najczęstszymi przyczynami ostrego zapalenia wątroby, a WZW typu C jest najczęstszą przyczyną przewlekłego zapalenia wątroby.¹

Wirusowe zapalenie wątroby typu A

Wirus zapalenia wątroby typu A (HAV) jest najczęstszą przyczyną ostrego wirusowego zapalenia wątroby. HAV przenosi się głównie drogą pokarmową (fekalno-oralną), gdy dochodzi do spożycia pokarmu lub wody skażonej odchodami zawierającymi wirusa. Wirus ten może również rozprzestrzeniać się przez bliski kontakt z osobą zakażoną.¹²

Najczęstszą przyczyną WZW typu A jest zatrucie pokarmowe. Może ono wystąpić, jeśli spożywasz żywność lub pijesz wodę zawierającą śladowe ilości zanieczyszczonych odchodów. Możesz również zachorować poprzez dzielenie się igłami lub uprawiając seks bez zabezpieczenia z osobą zakażoną wirusem.¹

Wirusowe zapalenie wątroby typu B

Wirus zapalenia wątroby typu B (HBV) jest wirusem DNA i należy do rodziny Hepadnaviridae. HBV może być wykryty w surowicy, nasieniu, wydzielinie pochwowej, ślinie i łzach, nawet na niższym poziomie, ale nie znajduje się w kale, moczu ani pocie. Jest przenoszony drogą parenteralną i seksualną, gdy człowiek ma kontakt z błonami śluzowymi lub płynami ustrojowymi zakażonych osób.¹

WZW typu B może rozprzestrzeniać się przez niezabezpieczony seks, dzielenie się igłami lub strzykawkami lub podczas porodu, kiedy może zostać przeniesione na noworodka.¹ Ryzyko rozwoju przewlekłego zakażenia HBV u zakażonych starszych dzieci i dorosłych wynosi około 5-10%.²

Szacuje się, że na całym świecie przewlekle zakażonych HBV jest 240 milionów ludzi. Główny rezerwuar HBV w Stanach Zjednoczonych stanowi od 850 000 do 2,2 miliona osób z przewlekłym zakażeniem HBV.²³

Ryzyko rozwoju przewlekłego zakażenia HBV jest bezpośrednio związane z wiekiem, w którym osoba po raz pierwszy zostaje narażona na kontakt z wirusem HBV. Ponad 90% zakażonych noworodków i niemowląt rozwinie przewlekłe zakażenie HBV, do 50% zakażonych dzieci (1-5 lat) rozwinie przewlekłe zakażenie HBV, a 5-10% zakażonych dorosłych rozwinie przewlekłe zakażenie HBV (to znaczy, że 90% osób wyzdrowieje).¹

Wirusowe zapalenie wątroby typu C

Wirus zapalenia wątroby typu C (HCV) jest wirusem RNA i należy do rodziny Flaviviridae z 1 serotypem, ale co najmniej 6 głównymi genotypami i ponad 80 podtypami.¹

Najczęstszym sposobem zarażenia się WZW typu C w USA jest dzielenie się igłami i strzykawkami do wstrzykiwania dożylnych narkotyków. Jesteś również zagrożony, gdy wykonujesz tatuaż lub piercing ciała przy użyciu niesterylnego sprzętu.¹

Przewlekłe zakażenie rozwija się u 50-60% pacjentów z zapaleniem wątroby typu C, a co najmniej 75% przypadków ostrego zapalenia wątroby typu C przechodzi w stan przewlekły.¹²

Wirusowe zapalenie wątroby typu D

Wirus zapalenia wątroby typu D (HDV) jest wirusem RNA i pojedynczym gatunkiem w rodzinie Deltaviridae. Zawiera antygen delta zapalenia wątroby i nić RNA oraz wymaga obecności i pomocy wirusa zapalenia wątroby typu B do replikacji.¹

Możesz zarazić się WZW typu D, jeśli już masz WZW typu B lub masz kontakt z oboma wirusami jednocześnie. WZW typu D rozprzestrzenia się przez niezabezpieczony seks i dzielenie się igłami.¹

Uważa się, że dzielenie się skażonymi igłami podczas przyjmowania narkotyków dożylnych jest najczęstszym sposobem przenoszenia HDV.¹ WZW typu D występuje tylko u osób już zakażonych WZW typu B.¹

Wirusowe zapalenie wątroby typu E

Wirus zapalenia wątroby typu E (HEV) jest nieotoczkowym wirusem RNA i pojedynczym gatunkiem w rodzinie Caliciviridae rodzaju Herpesvirus. Głównym sposobem przenoszenia HEV jest droga fekalno-oralna.¹

WZW typu E nie jest zaraźliwe. Możesz mieć kontakt z wirusem pijąc wodę zawierającą ślady kału od osoby z wirusem, jedząc niedogotowane mięso lub rodząc się osobie, która ma wirusa.¹

HEV jest główną przyczyną enteralnie przenoszonego zapalenia wątroby non-A, non-B (NANB).¹

Rzadko wirus zapalenia wątroby typu E powoduje przewlekłe zapalenie wątroby u osób z osłabionym układem odpornościowym.¹

Inne wirusy powodujące WZW

Wirus zapalenia wątroby typu G (HGV), obecnie oznaczony jako ludzki pegiwirus (HPgV-1), jest wirusem RNA i członkiem rodziny Flaviviridae. Głównym sposobem przenoszenia jest poprzez zakażoną krew i produkty krwiopochodne, ale kontakt seksualny i transmisja pionowa również występują.¹

Cytomegalowirus (CMV), wirus Epsteina-Barr (EBV) i inne wirusy opryszczki również mogą wywoływać zapalenie wątroby. Ten bardzo zaraźliwy wirus często powoduje ostre zapalenie wątroby i może prowadzić do przewlekłego zapalenia wątroby.¹²

Nieinfekcyjne przyczyny WZW

Chociaż WZW jest najczęściej wynikiem infekcji, inne czynniki mogą powodować tę chorobę. Obejmują one autoimmunologiczne zapalenie wątroby i zapalenie wątroby, które występuje jako wtórny skutek stosowania leków, narkotyków, toksyn i alkoholu.¹

Alkoholowe zapalenie wątroby

Nadmierne spożycie alkoholu może powodować uszkodzenie wątroby i stan zapalny. Może to być również określane jako alkoholowe zapalenie wątroby.¹

Alkoholowe zapalenie wątroby jest spowodowane nadmiernym piciem alkoholu, co szkodzi wątrobie. Może prowadzić do bliznowacenia wątroby (marskości), raka wątroby i niewydolności wątroby.¹

Jest to najczęstsza przyczyna marskości wątroby w Stanach Zjednoczonych.¹

Niealkoholowa stłuszczeniowa choroba wątroby

Niealkoholowa stłuszczeniowa choroba wątroby (NAFLD), obecnie nazywana stłuszczeniową chorobą wątroby związaną z dysfunkcją metaboliczną (MASLD), to stan, w którym masz nadmiar tłuszczu w wątrobie, powodujący zapalenie wątroby.¹

MASLD jest najczęstszą przyczyną chorób wątroby na świecie, z szacowaną częstością występowania na poziomie 25%.¹

Kryteria diagnostyczne stłuszczeniowej choroby wątroby związanej z dysfunkcją metaboliczną (MASLD) obejmują obecność steatozy wątroby w kontekście co najmniej 1 z następujących czynników ryzyka: nadwaga lub otyłość, dyslipidemia, insulinooporność, nadciśnienie.¹

Toksyczne zapalenie wątroby

Inne toksyczne przyczyny zapalenia wątroby obejmują niewłaściwe stosowanie leków i narażenie na toksyny.¹

Zapalenie wątroby wywołane lekami jest rzadkie, ale jest spowodowane nadmierną lub szkodliwą ilością witamin, leków lub suplementów.¹

Różne rodzaje leków mogą powodować zapalenie wątroby wywołane przez leki, w tym: acetaminofen lub paracetamol (w lekach przeciwgorączkowych i przeciwbólowych), który jest najczęstszą przyczyną piorunującego zapalenia wątroby wywołanego przez leki, stanowiąc około 50% wszystkich przypadków ostrej niewydolności wątroby w USA.²

Wiele leków, w tym izoniazyd, metotreksat, metylodopa, nitrofurantoina, tamoksyfen, amiodaron i rzadko acetaminofen, może powodować przewlekłe zapalenie wątroby.¹

Autoimmunologiczne zapalenie wątroby

W niektórych przypadkach układ odpornościowy myli wątrobę z czymś szkodliwym i atakuje ją. Powoduje to ciągły stan zapalny, który może wahać się od łagodnego do ciężkiego, często utrudniając funkcjonowanie wątroby.¹

Autoimmunologiczne zapalenie wątroby to przewlekła choroba spowodowana nieprawidłową odpowiedzią immunologiczną przeciwko komórkom wątroby.¹

Autoimmunologiczne zapalenie wątroby stanowi wysoki odsetek przypadków zapalenia wątroby niespowodowanego przez wirusy ani stłuszczeniowe zapalenie wątroby.¹

Nie jest do końca jasne, co powoduje autoimmunologiczne zapalenie wątroby, ale badacze uważają, że zarówno geny, jak i czynniki środowiskowe (takie jak leki lub wirusy) mogą odgrywać rolę.¹

Genetyczne przyczyny WZW

Genetyczne przyczyny zapalenia wątroby obejmują niedobór alfa-1-antytrypsyny, hemochromatozę i chorobę Wilsona.¹

Choroba Wilsona to rzadkie schorzenie genetyczne, które występuje, gdy w organizmie znajduje się zbyt dużo miedzi. Wysokie stężenie miedzi w wątrobie powoduje stan zapalny.¹

Hemochromatoza, pierwotna hemochromatoza to rzadka choroba genetyczna, która powoduje, że organizm wchłania zbyt dużo żelaza.¹

Niedobór alfa-1-antytrypsyny (A1AT) jest spowodowany mutacjami w genie SERPINA1, których istnieje co najmniej 150 alleli.¹

Inne przyczyny WZW

Zapalenie wątroby może wynikać również z różnych innych przyczyn, takich jak:¹

Niedokrwienne zapalenie wątroby wynika ze zmniejszonego przepływu krwi do wątroby, jak w przypadku wstrząsu, niewydolności serca lub niewydolności naczyniowej.¹
Zaburzenia dróg żółciowych, takie jak choledocholitiaza i zapalenie dróg żółciowych.¹
Zespół Budda-Chiariego to rzadkie zaburzenie naczyniowe definiowane jako niedrożność dróg odpływu żylnego wątroby, niezależnie od mechanizmu, pod warunkiem, że niedrożność nie jest związana z chorobą serca, chorobą osierdzia ani zespołem niedrożności zatokowej.¹
Cholestaza. Ten stan powoduje zastój żółci w wątrobie, wywołując stan zapalny.¹

Następstwa zapalenia wątroby

Zapalenie wątroby może mieć szereg poważnych następstw, szczególnie gdy przechodzi w postać przewlekłą. Najważniejsze z nich to:¹²

Marskość wątroby – długotrwałe zapalenie prowadzi do postępującego włóknienia tkanki wątrobowej
Rak wątroby – szczególnie u osób z przewlekłym zakażeniem HBV lub HCV
Niewydolność wątroby – ciężkie uszkodzenie wątroby prowadzące do zaburzenia jej funkcji
Powikłania pozawątrobowe – niektóre typy WZW, takie jak B i C, mogą powodować objawy poza wątrobą

Pacjenci z przewlekłym zakażeniem HBV mają znacznie wyższe ryzyko wystąpienia raka wątrobowokomórkowego (HCC).¹ Wirusowe zapalenie wątroby jest główną przyczyną raka wątroby, dlatego osoby z przewlekłym zapaleniem wątroby typu B lub C wymagają monitorowania, nawet jeśli czują się zdrowe.¹

Czynniki ryzyka WZW

Istnieje wiele czynników ryzyka, które zwiększają prawdopodobieństwo zakażenia wirusami zapalenia wątroby:¹²

Nieszczepienie się przeciwko WZW typu A i B
Dożylne przyjmowanie narkotyków i dzielenie się igłami
Niebezpieczne praktyki seksualne
Transfuzje krwi (przed wprowadzeniem odpowiednich testów)
Praca w zawodach medycznych (narażenie na zakażoną krew)
Tatuaże lub piercing wykonywane w niehigienicznych warunkach
Podróże do krajów o wysokiej endemiczności
Kontakty z osobą zakażoną
Pobyt w instytucjach zbiorowego zamieszkania

Osoby z WZW są bardziej narażone na ciężki przebieg choroby, jeśli mają już uszkodzoną wątrobę z innych przyczyn, są starsze lub mają inne choroby współistniejące.¹

Współwystępowanie zakażenia HIV z WZW typu B lub C znacznie pogarsza rokowanie i przyspiesza postęp choroby wątroby.²¹

Podsumowanie przyczyn WZW

Wirusowe zapalenie wątroby jest najczęściej wywoływane przez pięć głównych wirusów hepatotropowych: HAV, HBV, HCV, HDV i HEV, z których każdy ma swój specyficzny sposób transmisji, przebieg kliniczny i potencjalne powikłania. Oprócz czynników wirusowych, WZW może być spowodowane przez toksyny (alkohol, leki, chemikalia), choroby autoimmunologiczne i genetyczne zaburzenia metabolizmu.

Przewlekłe WZW, szczególnie typu B i C, stanowi poważny problem zdrowotny ze względu na ryzyko rozwoju marskości i raka wątroby. Zrozumienie etiologii WZW jest kluczowe dla skutecznej profilaktyki, wczesnego wykrywania i leczenia tej potencjalnie niebezpiecznej choroby.¹¹

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Materiały źródłowe

#1 Hepatitis: What It Is, Symptoms, Transmission & Treatments
https://my.clevelandclinic.org/health/diseases/hepatitis
Hepatitis happens when something causes inflammation in your liver. Many things can injure your liver and trigger hepatitis. Certain viral infections cause hepatitis. But you also can develop it if you have diseases that affect your liver or you’re exposed to toxins like chemicals, alcohol or drugs. […] Many things can cause hepatitis. The most common cause is exposure to viruses. Health conditions that damage your liver can cause hepatitis. So can exposure to toxins like alcohol, drugs including medications and chemicals. […] Any disease that affects your liver can cause hepatitis. Conditions that may cause hepatitis are: Cholestasis. This condition causes bile to back up in your liver, causing inflammation. Cytomegalovirus (CMV). Herpes viruses cause CMV. It can lead to liver issues (CMV hepatitis) if you have a weak immune system. Epstein-Barr virus. This very contagious virus often causes acute hepatitis and can lead to chronic hepatitis. Hemochromatosis. Primary hemochromatosis is a rare genetic condition that causes your body to absorb too much iron. Metabolic dysfunction-associated steatotic liver disease (MASLD). In this condition, you have excess fat in your liver, causing hepatitis. Wilson disease. This rare genetic condition happens when you have too much copper in your body. High copper levels in your liver cause inflammation.
#1 Viral Hepatitis – StatPearls – NCBI Bookshelf
https://www.ncbi.nlm.nih.gov/books/NBK554549/
Hepatitis is defined as inflammation of the liver that can result from a variety of causes, such as heavy alcohol use, autoimmune disorders, drugs, or toxins. However, the most frequent cause of hepatitis is due to a viral infection, referred to as „viral hepatitis.” Several different strains of viruses can cause hepatitis. In the United States, the most common types of viral hepatitis are hepatitis A, hepatitis B, and hepatitis C. The other types of viral hepatitis are hepatitis D and E, which are encountered less frequently. […] Based on the etiology of hepatitis, the severity can range from mild, nearly asymptomatic, to severe illness requiring liver transplantation. Hepatitis can be further classified into „acute” and „chronic” based on the duration of the inflammation in the liver. […] The majority of cases of viral hepatitis result from hepatotropic viruses A, B, C, D, and E. It is unclear whether the hepatitis G virus (HGV) is pathogenic in humans. Other less common causes of viral hepatitis are cytomegalovirus (CMV), Epstein-Barr virus(EBV), herpes simplex virus (HSV), and varicella-zoster virus (VZV). These are non-heterotropic viruses that usually do not primarily target the liver and rarely cause hepatitis in the immunocompetent state.
#1 Viral Hepatitis: Background, Pathophysiology, Etiology
https://emedicine.medscape.com/article/775507-overview
Hepatitis viruses A, B, C, D (HAV, HBV, HCV, HDV [which requires coexisting HBV infection]), and E (HEV) cause the majority of clinical cases of viral hepatitis. […] HAV, HBV, HCV, and HDV are the only hepatitis viruses endemic to the United States; HAV, HBV, and HCV are responsible for more than 90% of US cases of acute viral hepatitis. Whereas HAV and HBV are the most common causes of acute hepatitis in the United States, HCV is the most common cause of chronic hepatitis. […] The major reservoir of HBV in the United States consists of the 850,000 to 2.2 million people with chronic HBV infection. […] The risk of chronic HBV infection in infected older children and adults approaches 5-10%. […] Chronic infection develops in 50-60% of patients with hepatitis C. […] Patients with chronic HBV infection are at significantly higher risk for HCC.
#1 Hepatitis A – Symptoms and causes – Mayo Clinic
https://www.mayoclinic.org/diseases-conditions/hepatitis-a/symptoms-causes/syc-20367007
Hepatitis A is a highly contagious liver infection caused by the hepatitis A virus. The virus is one of several types of hepatitis viruses that cause liver inflammation and affect your liver’s ability to function. […] Hepatitis A is caused by a virus that infects liver cells and causes inflammation. The inflammation can affect how your liver works and cause other symptoms of hepatitis A. […] The virus spreads when infected stool, even just tiny amounts, enters the mouth of another person (fecal-oral transmission). You may get hepatitis A when you eat or drink something contaminated with infected stool. You may also get the infection through close contact with a person who has hepatitis A. The virus can live on surfaces for a few months. The virus does not spread through casual contact or by sneezing or coughing.
#1 Viral Hepatitis: What It Is, Symptoms, Causes & Treatment
https://my.clevelandclinic.org/health/diseases/4245-hepatitis-viral-hepatitis-a-b–c
Viral hepatitis happens when you have exposure to any of the viruses that cause it. That can happen if you have contact with bodily fluids like blood and pee from someone who has the virus. […] The most common cause for hepatitis A is food poisoning. That can happen if you eat food or drink water that contains traces of contaminated poop. You can also get it from sharing needles or having unprotected sex with someone who has the virus. […] Hepatitis B can spread through unprotected sex, sharing needles or syringes, or during childbirth, when it can pass to the newborn. […] The most common way to get hepatitis C in the U.S. is sharing needles and syringes to inject intravenous drugs. You’re also at risk when getting a tattoo or body piercing with unsterile equipment. […] You can get hepatitis D if you already have hepatitis B or have exposure to both viruses at the same time. Hepatitis D spreads through unprotected sex and sharing of needles. […] Hepatitis E isn’t contagious. You may have exposure to the virus by drinking water that contains traces of poop from someone with the virus, eating undercooked meat or being born to someone who has the virus.
#1 Viral Hepatitis – StatPearls – NCBI Bookshelf
https://www.ncbi.nlm.nih.gov/books/NBK554549/
Hepatitis A, B, C, and D are endemic to the United States, with hepatitis A, B, and C viruses causing 90% of acute viral hepatitis and hepatitis C being the most common cause of chronic hepatitis. […] Hepatitis B virus (HBV) is a DNA virus and a member of the Hepadnaviridae family. […] HBV can be detected in serum, semen, vaginal mucus, saliva, and tears, even at a lower level but is not found in stool, urine, or sweat. It is transmitted parenterally and sexually when individuals come in contact with mucous membranes or body fluids of infected individuals. […] Hepatitis C virus (HCV) is an RNA virus and is a member of the Flaviviridae family with 1 serotype but at least 6 major genotypes and more than 80 subtypes. […] Hepatitis D virus (HDV) is an RNA virus and a single species in the Deltaviridae family. It contains the hepatitis D antigen and RNA strand and requires the presence and help of the hepatitis B virus for replication.
#1 Hepatitis B Foundation: Acute vs. Chronic Hepatitis B Infection
https://www.hepb.org/what-is-hepatitis-b/what-is-hepb/acute-vs-chronic/
People who test positive for the hepatitis B virus for more than six months (after their first blood test result) are diagnosed as having a chronic infection. […] The risk of developing a chronic hepatitis B infection is also directly related to the age at which one first becomes exposed to the hepatitis B virus. […] 90% of infected newborns and babies will develop a chronic hepatitis B infection. […] Up to 50% of infected children (1-5 years) will develop a chronic hepatitis B infection. […] 5-10% of infected adults will develop a chronic hepatitis B infection (that is, 90% will recover). […] The good news is that most people with chronic hepatitis B should expect to live a long and healthy life. […] There are effective drug therapies that can control and even stop the hepatitis B virus from further damaging a liver. […] Although the risk of developing a serious liver disease or liver cancer is higher for those living with chronic hepatitis B than those who are not infected, there are still many simple things a person can do to help reduce their risks.
#1 Viral Hepatitis: Background, Pathophysiology, Etiology
https://emedicine.medscape.com/article/775507-overview
An estimated 240 million people worldwide are chronically infected with HBV. […] The vast majority of HBV cases around the world result from perinatal transmission. […] The sharing of contaminated needles in IDU is thought to be the most common means of transmitting HDV. […] HEV is the primary cause of enterally transmitted NANB hepatitis.
#1 Types of Hepatitis | NYU Langone Health
https://nyulangone.org/conditions/hepatitis/types
Hepatitis means inflammation of the liver. Often, a viral infection is the cause of this inflammation. The viruses known as hepatitis A, hepatitis B, and hepatitis C are the most common causes. […] Other viruses, certain medications and toxins, some autoimmune conditions, and long-term, heavy use of alcohol can also cause hepatitis. […] Hepatitis A, B, C, D, and E are each caused by a specific type of hepatitis virus. […] Hepatitis B is a liver infection caused by the hepatitis B virus. […] Hepatitis C is a liver infection caused by the hepatitis C virus. […] Hepatitis D, also known as hepatitis delta, is a liver infection caused by the hepatitis D virus. Only people who have hepatitis B can become infected with hepatitis D. […] Hepatitis E is a liver infection caused by the hepatitis E virus.
#1 Viral Hepatitis – StatPearls – NCBI Bookshelf
https://www.ncbi.nlm.nih.gov/books/NBK554549/
Hepatitis E virus (HEV) is a non-enveloped RNA virus and a single species in the Caliciviridae family of the Herpesvirus genus. The primary transmission mode of the HEV is the fecal-oral route. […] Hepatitis G virus (HGV), now designated human pegivirus (HPgV-1), is an RNA virus and is a member of the Flaviviridae family. The primary mode of transmission is through infected blood and blood products, but sexual contact and vertical transmission occur as well.
#1 Overview of Chronic Hepatitis – Liver and Gallbladder Disorders – Merck Manual Consumer Version
https://www.merckmanuals.com/home/liver-and-gallbladder-disorders/hepatitis/overview-of-chronic-hepatitis
Chronic hepatitis is inflammation of the liver that lasts at least 6 months. […] Common causes include hepatitis B and C viruses and certain medications. […] The most common causes of chronic hepatitis are Hepatitis C virus, Hepatitis B virus, Fatty liver not due to alcohol use, and Alcohol-related liver disease. […] Hepatitis C virus causes about 60 to 70% of cases of chronic hepatitis, and at least 75% of acute hepatitis C cases become chronic. […] About 5 to 10% of hepatitis B cases in adults become chronic, sometimes with hepatitis D coinfection. […] Rarely, hepatitis E virus causes chronic hepatitis in people with a weakened immune system. […] Autoimmune hepatitis, medications, alpha-1 antitrypsin deficiency, celiac disease, hemochromatosis, primary biliary cholangitis, a thyroid disorder, and Wilson disease can also cause chronic hepatitis. […] Certain medications can cause chronic hepatitis, particularly when they are taken for a long time. […] No one knows exactly why a particular virus or medication causes chronic hepatitis in some people but not in others or why the degree of severity varies.
#1 Hepatitis: What Is It? Types, Symptoms, Causes, and More
https://www.healthline.com/health/hepatitis
Hepatitis is an inflammation of the liver. It may be caused by viral infection, alcohol consumption, several health conditions, or even some medications. […] Hepatitis refers to an inflammatory condition of the liver. It is commonly the result of a viral infection, but there are other possible causes of hepatitis. […] These include autoimmune hepatitis and hepatitis that occurs as a secondary result of medications, drugs, toxins, and alcohol. […] The five main viral classifications of hepatitis are hepatitis A, B, C, D, and E. A different virus is responsible for each type of viral hepatitis. […] Although hepatitis is most commonly the result of an infection, other factors can cause the condition. […] Excess alcohol consumption can cause liver damage and inflammation. This may also be referred to as alcoholic hepatitis. […] Other toxic causes of hepatitis include misuse of medications and exposure to toxins. […] In some cases, the immune system mistakes the liver as harmful and attacks it. This causes ongoing inflammation that can range from mild to severe, often hindering liver function.
#1
https://www.aurorahealthcare.org/services/gastroenterology-colorectal-surgery/non-viral-hepatitis
Non-viral hepatitis is an inflammation of the liver that can cause scarring on the liver (cirrhosis), liver cancer, liver failure and death. […] Toxic hepatitis is caused by chemicals, drugs (prescription and over-the-counter) and nutritional supplements. […] Alcoholic hepatitis is caused by drinking too much alcohol, which harms the liver. […] Autoimmune hepatitis is caused by the immune system attacking the liver. The immune system can attack the liver for unknown reasons, causing inflammation, liver scarring, liver cancer and liver failure. Some diseases and certain toxic substances and drugs can cause this to happen.
#1 Hepatitis Causes, Symptoms, Diagnosis and Treatment – Cura4U
https://cura4u.com/conditions/hepatitis
Hepatitis is classified as either an acute (short-term) or chronic (long-term) infection. […] Causes of hepatitis are broadly categorized into two types: Infectious causes and Non-infectious causes. […] Infectious Causes are the most common cause of hepatitis, caused by viruses, bacteria, fungi, and parasites. Amongst them, more than 50% of cases are caused by viruses. […] Non-Infectious Causes include alcohol, drugs, metabolic diseases, and autoimmune diseases. […] Excessive alcohol use is a significant cause of alcoholic hepatitis and the leading cause of cirrhosis in the United States. […] Ischemic hepatitis is caused by a reduction in blood flow to the liver, which can occur due to shock, heart failure, or vascular insufficiency. […] Autoimmune hepatitis is liver inflammation caused by your immune system attacking liver cells. The specific cause of autoimmune hepatitis is unknown, but it appears that genetic and environmental factors interact over time to develop the condition. […] The prognosis of hepatitis varies depending upon the causative agent.
#1 Nonviral hepatitis: common causes and their management | Medicine Today
https://medicinetoday.com.au/mt/2022/may/feature-article/nonviral-hepatitis-common-causes-and-their-management
The most common causes of nonviral liver disease that may present as a hepatitis include metabolic-associated fatty liver disease (MAFLD), alcohol-related liver disease (ALD) and drug-induced liver injury (DILI). […] Given the significant therapeutic advances for chronic viral hepatitis in recent years, the proportion of nonviral liver disease as a cause of hepatitis is increasing, as is the prevalence. […] MAFLD, previously referred to as non-alcoholic fatty liver disease (NAFLD), is the most common cause of liver disease worldwide, with an estimated prevalence of 25%. […] Alcoholic hepatitis is an uncommon presentation of ALD and is characterised by the onset of jaundice and moderate elevations of AST levels that are greater than elevations of ALT levels, in patients with recent high-level alcohol consumption.
#1 Overview of Chronic Hepatitis – Hepatic and Biliary Disorders – MSD Manual Professional Edition
https://www.msdmanuals.com/professional/hepatic-and-biliary-disorders/hepatitis/overview-of-chronic-hepatitis
Criteria for the diagnosis of metabolic dysfunction-associated steatotic liver disease (MASLD) include the presence of steatosis in the liver in the setting of at least 1 of the following risk factors: Overweight or obesity, Dyslipidemia, Insulin resistance, Hypertension. […] Metabolic dysfunction-associated steatohepatitis (MASH) is the progressive form of MASLD that causes chronic hepatitis. […] Alcohol-related liver disease (a combination of fatty liver, diffuse liver inflammation, and liver necrosis) results from excess alcohol consumption. […] Autoimmune hepatitis (immune-mediated hepatocellular injury) accounts for a high proportion of hepatitis not caused by viruses or steatohepatitis. […] Many drugs, including isoniazid, methotrexate, methyldopa, nitrofurantoin, tamoxifen, amiodarone, and rarely acetaminophen, can cause chronic hepatitis. […] Less often, chronic hepatitis results from alpha-1 antitrypsin deficiency, celiac disease, a thyroid disorder, hereditary hemochromatosis, or Wilson disease.
#1
https://healthmatch.io/liver-disease/fulminant-hepatitis
Fulminant hepatitis can be caused by certain viruses, including hepatitis A, B, D, or E. […] The two most common causes are drug-induced and viruses. […] Drug-induced hepatitis is rare but is caused by an over-excessive or harmful amount of vitamins, medicines, or supplements. […] In the case of acute liver failure, the cause is due to a sudden excess amount of drugs or certain drug interactions that cause acute and abrupt elevation of the blood plasma level of this medication. […] Various types of medications can cause drug-induced fulminant hepatitis, including: Acetaminophen or paracetamol (in fever and pain medications) is the most common cause of drug-induced fulminant hepatitis, accounting for around 50% of all acute liver failure cases in the US. […] Fulminant hepatitis is a late-stage liver condition characterized by rapid deterioration of normal liver functions and damage to the liver tissues, which leads to encephalopathy. Causes can vary, but two of the most commonly known ones are viral hepatitis conditions or drug-induced hepatitis, often from an overdose of acetaminophen.
#1 Hepatitis – Wikipedia
https://en.wikipedia.org/wiki/Hepatitis
Chronic hepatitis B management aims to control viral replication, which is correlated with progression of disease. […] Autoimmune hepatitis is a chronic disease caused by an abnormal immune response against liver cells. […] Genetic causes of hepatitis include alpha-1-antitrypsin deficiency, hemochromatosis, and Wilson’s disease. […] Ischemic hepatitis results from reduced blood flow to the liver as in shock, heart failure, or vascular insufficiency. […] Hepatitis can also occur in neonates and is attributable to a variety of causes, some of which are not typically seen in adults.
#1 Hepatitis: Causes and Risk Factors
https://www.verywellhealth.com/hepatitis-causes-and-risk-factors-4689127
Toxic hepatitis is when substances damage the liver and cause it to swell. The primary drivers behind toxic hepatitis are alcohol, toxic chemicals, and certain medications. […] Autoimmune hepatitis is when your own bodys defenses attack your liver, causing it to swell and become damaged. Its unclear exactly what causes autoimmune hepatitis, but researchers think both genes and environmental factors (like medications or viruses) could play a role. […] A persons health history might also affect the chances he or she will develop hepatitis. […] Health risk factors for hepatitis include: Not being vaccinated against viral hepatitis, specifically HAV and HBV (there is no vaccine for HBC).
#1 Nonviral hepatitis: common causes and their management | Medicine Today
https://medicinetoday.com.au/mt/2022/may/feature-article/nonviral-hepatitis-common-causes-and-their-management
Alpha-1 antitrypsin (A1AT) deficiency is due to mutations in the SERPINA1 gene, of which there are at least 150 alleles. […] Budd-Chiari syndrome is a rare vascular disorder defined as hepatic venous outflow tract obstruction, independent of the mechanism, provided the obstruction is not related to cardiac disease, pericardial disease or sinusoidal obstruction syndrome.
#1 Causes of Hepatitis – Hepatic and Biliary Disorders – Merck Manual Professional Edition
https://www.merckmanuals.com/professional/hepatic-and-biliary-disorders/hepatitis/causes-of-hepatitis
Hepatitis is inflammation of the liver, which can have a variety of etiologies. […] At least 5 specific viruses appear to be responsible for hepatitis (see table Characteristics of Hepatitis Viruses). Other unidentified viruses probably also cause acute viral hepatitis. […] Common causes of hepatitis include specific hepatitis viruses, alcohol, metabolic dysfunction-associated steatotic liver disease (MASLD) [previously called nonalcoholic fatty liver disease (NAFLD)], and drugs (eg, isoniazid). […] Less common causes of hepatitis include autoimmune disorders, genetic liver disorders, other viral infections (eg, infectious mononucleosis, yellow fever, cytomegalovirus infection), and leptospirosis.
#1 Nonviral hepatitis: common causes and their management | Medicine Today
https://medicinetoday.com.au/mt/2022/may/feature-article/nonviral-hepatitis-common-causes-and-their-management
DILI is responsible for 3 to 5% of hospital admissions for jaundice and is the most frequent cause of acute liver failure in Western countries. […] Biliary tract disorders, such as choledocholithiasis and cholangitis, are commonly encountered in primary care and may present with a hepatitis pattern of liver enzyme derangement. […] Autoimmune liver diseases represent uncommon and heterogeneous conditions that, if left untreated, may progress to cirrhosis. […] Autoimmune hepatitis is a chronic inflammatory syndrome that can present at any age and is more common in women. […] Hereditary haemochromatosis is a common autosomal recessive disorder, affecting one in 300 people in Australia. […] Wilson’s disease is a rare genetic disorder characterised by excess copper accumulation due to a variety of mutations in the ATP7B gene.
#1 What Causes Hepatitis? | NIH News in Health
https://newsinhealth.nih.gov/2022/07/what-causes-hepatitis
Hepatitis is inflammation of the liver. What causes hepatitis isnt always known. […] Viruses are the most common culprit. There are five known viruses that cause the condition: hepatitis A, B, C, D, and E. Hepatitis A and E are usually spread through contaminated food or water. Hepatitis B, C, and D are contracted through exposure to infected blood and possibly other body fluids. […] Other causes of hepatitis include heavy alcohol use, toxins, certain medications, and autoimmune diseases. Autoimmune diseases happen when the bodys protective response to illness or disease goes awry. This can cause your body to attack your own cells and organs, like the liver. […] Chronic hepatitis can have serious complications. It can damage your liver and lead to liver failure. It can also cause liver cancer.
#1 A Visual Guide to Hepatitis A, B, C
https://www.webmd.com/hepatitis/ss/slideshow-hepatitis-overview
Hepatitis is an inflammation of the liver. It may be caused by drugs, alcohol use, or certain medical conditions. But in most cases, it’s caused by a virus. This is known as viral hepatitis, and the most common forms are hepatitis A, B, and C. […] Many adults who get hepatitis B have mild symptoms for a short time and then get better on their own. But some people are not able to clear the virus from the body, which causes a long-term infection. Nearly 90% of infants who get the virus will carry it for life. Over time, hepatitis B can lead to serious problems, such as liver damage, liver failure, and liver cancer. […] About 25% of people who get hepatitis C defeat the virus after a short-term infection. The rest will carry the virus in their body for the long term. Chronic hepatitis C can cause very serious complications, including liver failure and liver cancer. There are effective treatments for the virus, though. […] Viral hepatitis is the top cause of liver cancer, so people with chronic hepatitis B or C need monitoring even if they feel healthy.
#1 Hepatitis B & C
https://www.hiv.gov/hiv-basics/staying-in-hiv-care/other-related-health-issues/hepatitis-b-and-c
Hepatitis means inflammation of the liver. This condition is often caused by a virus. In the United States, the most common causes of viral hepatitis are hepatitis B virus (HBV) and hepatitis C virus (HCV). […] Given the risks of hepatitis B or hepatitis C coinfection to people with HIV, it is important to understand these risks, take steps to prevent infection, know your status, and, if necessary, get medical care from a health care provider who is experienced in treating people who are coinfected with HIV and HBV, or HIV and HCV. […] About 2% of people with HIV in the United States are coinfected with HBV. People with HIV are at greater risk for complications and death from HBV infection. […] HCV infection is common among people with HIV who also inject drugs. Nearly 75% of people with HIV who report a history of injection drug use are co-infected with HCV. People with HIV are at greater risk for complications and death from HCV infection.
#1 Risks and causes – The Hepatitis C Trust
https://www.hepctrust.org.uk/about-hep-c/risks-and-causes/
Hepatitis C prevalence is much higher among people who are HIV-positive than those who are not. […] Sharing personal hygiene products such as toothbrushes, razors or hair and nail clippers with someone carrying the virus may pose a potential risk of contracting hepatitis C. […] The risks of contracting hepatitis C through tattooing are mainly associated with reused and unsterilised needles, although the virus has also been found in tattooing ink.
#1
https://www.who.int/health-topics/hepatitis
Hepatitis is an inflammation of the liver that is caused by a variety of infectious viruses and noninfectious agents leading to a range of health problems, some of which can be fatal. There are five main strains of the hepatitis virus, referred to as types A, B, C, D and E. While they all cause liver disease, they differ in important ways including modes of transmission, severity of the illness, geographical distribution and prevention methods. In particular, types B and C lead to chronic disease in hundreds of millions of people and together are the most common cause of liver cirrhosis, liver cancer and viral hepatitis-related deaths. An estimated 354 million people worldwide live with hepatitis B or C, and for most, testing and treatment remain beyond reach. […] Hepatitis D (HDV) is only found in people already infected with hepatitis B (HBV); however, the dual infection of HBV and HDV can cause a more serious infection and poorer health outcomes, including accelerated progression to cirrhosis.
#1 Hepatitis B | Hepatitis B | CDC
https://www.cdc.gov/hepatitis-b/index.html
Hepatitis B is a liver disease caused by the hepatitis B virus (HBV). […] Hepatitis B vaccination is recommended for adults at risk for HBV infection, including persons at risk.
#2 Hepatitis: What Is It? Types, Symptoms, Causes, and More
https://www.healthline.com/health/hepatitis
Hepatitis is an inflammation of the liver. It may be caused by viral infection, alcohol consumption, several health conditions, or even some medications. […] Hepatitis refers to an inflammatory condition of the liver. It is commonly the result of a viral infection, but there are other possible causes of hepatitis. […] These include autoimmune hepatitis and hepatitis that occurs as a secondary result of medications, drugs, toxins, and alcohol. […] The five main viral classifications of hepatitis are hepatitis A, B, C, D, and E. A different virus is responsible for each type of viral hepatitis. […] Although hepatitis is most commonly the result of an infection, other factors can cause the condition. […] Excess alcohol consumption can cause liver damage and inflammation. This may also be referred to as alcoholic hepatitis. […] Other toxic causes of hepatitis include misuse of medications and exposure to toxins. […] In some cases, the immune system mistakes the liver as harmful and attacks it. This causes ongoing inflammation that can range from mild to severe, often hindering liver function.
#2 Viral Hepatitis: Background, Pathophysiology, Etiology
https://emedicine.medscape.com/article/775507-overview
Hepatitis viruses A, B, C, D (HAV, HBV, HCV, HDV [which requires coexisting HBV infection]), and E (HEV) cause the majority of clinical cases of viral hepatitis. […] HAV, HBV, HCV, and HDV are the only hepatitis viruses endemic to the United States; HAV, HBV, and HCV are responsible for more than 90% of US cases of acute viral hepatitis. Whereas HAV and HBV are the most common causes of acute hepatitis in the United States, HCV is the most common cause of chronic hepatitis. […] The major reservoir of HBV in the United States consists of the 850,000 to 2.2 million people with chronic HBV infection. […] The risk of chronic HBV infection in infected older children and adults approaches 5-10%. […] Chronic infection develops in 50-60% of patients with hepatitis C. […] Patients with chronic HBV infection are at significantly higher risk for HCC.
#2 Causes of hepatitis A – Canada.ca
https://www.canada.ca/en/public-health/services/diseases/hepatitis-a/causes.html
Hepatitis A is a liver disease caused by the hepatitis A virus. Its different from other types of hepatitis, such as hepatitis B and C. […] Hepatitis A is most commonly spread when someone eats food or drinks water that contains the hepatitis A virus. […] Food and water become contaminated with the hepatitis A virus when they come in contact with feces from infected people. […] The hepatitis A virus can be found in sewage and untreated water.
#2 Overview of Chronic Hepatitis – Liver and Gallbladder Disorders – Merck Manual Consumer Version
https://www.merckmanuals.com/home/liver-and-gallbladder-disorders/hepatitis/overview-of-chronic-hepatitis
Chronic hepatitis is inflammation of the liver that lasts at least 6 months. […] Common causes include hepatitis B and C viruses and certain medications. […] The most common causes of chronic hepatitis are Hepatitis C virus, Hepatitis B virus, Fatty liver not due to alcohol use, and Alcohol-related liver disease. […] Hepatitis C virus causes about 60 to 70% of cases of chronic hepatitis, and at least 75% of acute hepatitis C cases become chronic. […] About 5 to 10% of hepatitis B cases in adults become chronic, sometimes with hepatitis D coinfection. […] Rarely, hepatitis E virus causes chronic hepatitis in people with a weakened immune system. […] Autoimmune hepatitis, medications, alpha-1 antitrypsin deficiency, celiac disease, hemochromatosis, primary biliary cholangitis, a thyroid disorder, and Wilson disease can also cause chronic hepatitis. […] Certain medications can cause chronic hepatitis, particularly when they are taken for a long time. […] No one knows exactly why a particular virus or medication causes chronic hepatitis in some people but not in others or why the degree of severity varies.
#2 Viral Hepatitis: Symptoms & Causes | NewYork-Presbyterian
https://www.nyp.org/digestive/liver-diseases/viral-hepatitis
Hepatitis (viral hepatitis) is the inflammation of the liver. Hepatitis is typically caused by infectious viruses like hepatitis A, B, or C, but alcohol, genetic disorders, or autoimmune issues can also cause it. […] There are five main viruses that cause hepatitis hepatitis A, B, C, D or E. But hepatitis can also be caused by other viruses, including cytomegalovirus, the Epstein-Barr virus, or herpes simplex virus. […] Hepatitis is caused by a virus, meaning it can be passed from one person to another, usually through the exchange of blood or bodily fluids, or through food or water thats been contaminated by feces. […] Hepatitis can also be caused by contracting other viruses, including cytomegalovirus, the Epstein-Barr virus, and herpes simplex virus.
#2
https://healthmatch.io/liver-disease/fulminant-hepatitis
Fulminant hepatitis can be caused by certain viruses, including hepatitis A, B, D, or E. […] The two most common causes are drug-induced and viruses. […] Drug-induced hepatitis is rare but is caused by an over-excessive or harmful amount of vitamins, medicines, or supplements. […] In the case of acute liver failure, the cause is due to a sudden excess amount of drugs or certain drug interactions that cause acute and abrupt elevation of the blood plasma level of this medication. […] Various types of medications can cause drug-induced fulminant hepatitis, including: Acetaminophen or paracetamol (in fever and pain medications) is the most common cause of drug-induced fulminant hepatitis, accounting for around 50% of all acute liver failure cases in the US. […] Fulminant hepatitis is a late-stage liver condition characterized by rapid deterioration of normal liver functions and damage to the liver tissues, which leads to encephalopathy. Causes can vary, but two of the most commonly known ones are viral hepatitis conditions or drug-induced hepatitis, often from an overdose of acetaminophen.
#2
https://www.who.int/health-topics/hepatitis
Hepatitis is an inflammation of the liver that is caused by a variety of infectious viruses and noninfectious agents leading to a range of health problems, some of which can be fatal. There are five main strains of the hepatitis virus, referred to as types A, B, C, D and E. While they all cause liver disease, they differ in important ways including modes of transmission, severity of the illness, geographical distribution and prevention methods. In particular, types B and C lead to chronic disease in hundreds of millions of people and together are the most common cause of liver cirrhosis, liver cancer and viral hepatitis-related deaths. An estimated 354 million people worldwide live with hepatitis B or C, and for most, testing and treatment remain beyond reach. […] Hepatitis D (HDV) is only found in people already infected with hepatitis B (HBV); however, the dual infection of HBV and HDV can cause a more serious infection and poorer health outcomes, including accelerated progression to cirrhosis.
#2 Hepatitis A: Background, Pathophysiology, Etiology
https://emedicine.medscape.com/article/177484-overview
One of the more common causes of acute hepatitis is hepatitis A virus (HAV) infection, which was isolated by Purcell in 1973. […] Most patients have no defined risk factors for hepatitis A. Risk factors for the acquisition of hepatitis A include the following: Personal contacts, Institutionalization, Occupation (eg, daycare), Foreign travel, Male homosexuality, Illicit parenteral drug use. […] Over the last century, improved sanitation and hygiene measures have resulted in a shift in the age group that carries the burden of hepatitis A. […] Individuals in the high-risk populations currently account for many sporadic cases of HAV infection. These groups include contacts of recently infected individuals, foreign travelers (particularly those to developing nations), male homosexuals, childcare workers, institutionalized individuals, and those living in poverty.
#2 Hepatitis B & C
https://www.hiv.gov/hiv-basics/staying-in-hiv-care/other-related-health-issues/hepatitis-b-and-c
Hepatitis means inflammation of the liver. This condition is often caused by a virus. In the United States, the most common causes of viral hepatitis are hepatitis B virus (HBV) and hepatitis C virus (HCV). […] Given the risks of hepatitis B or hepatitis C coinfection to people with HIV, it is important to understand these risks, take steps to prevent infection, know your status, and, if necessary, get medical care from a health care provider who is experienced in treating people who are coinfected with HIV and HBV, or HIV and HCV. […] About 2% of people with HIV in the United States are coinfected with HBV. People with HIV are at greater risk for complications and death from HBV infection. […] HCV infection is common among people with HIV who also inject drugs. Nearly 75% of people with HIV who report a history of injection drug use are co-infected with HCV. People with HIV are at greater risk for complications and death from HCV infection.
#3 Viral Hepatitis: Background, Pathophysiology, Etiology
https://emedicine.medscape.com/article/775507-overview
An estimated 240 million people worldwide are chronically infected with HBV. […] The vast majority of HBV cases around the world result from perinatal transmission. […] The sharing of contaminated needles in IDU is thought to be the most common means of transmitting HDV. […] HEV is the primary cause of enterally transmitted NANB hepatitis.