Hépatites virales

Hépatite B

Source: https://mksap18.acponline.org/app/topics/gi/mk18_a_gi_s6/mk18_a_gi_s6_2_2

Infection chronique à HBV

	HBsAg	anti-HBs	anti-HBc	HBeAg	anti-HBe	HBV DNA	ALAT	Prise en charge
Interprétation	Infection aiguë ou chronique	Infection résolue ou vaccination	Infection actuelle ou passée	Réplication active	Infection inactive ou mutant
Phase immunotolérante Âge < 30 ans	+			+	-	> 1 million	Normal	Absence d'inflammation hépatique. Suivi ALAT +/- alpha-FP/US. Exceptions: patients >40 ans, virémie >1 mio ET inflammation et fibrose
Phase immunoréactive HBeAg pos ou HBeAg nég	+	-	+ (IgG) OK ???	+	- (?)	> 20 000 IU/ml	↑	Inflammation et fibrose Traitement nécessaire.
	+	-	+ (IgG) OK ???	-	- (?)	> 2000 IU/ml
Hépatite B chronique inactive = porteur inactif	+	-	+ (IgG) OK ???	-	+	< 2000 IU/ml	Normal	Pas d'inflammation, fibrose variable Suivi de l'HBV DNA 3-4x/an
Hépatite B résolue	-	+	+ (IgG)	-	+/-	-	Normal	CAVE si immunosupression
Réactivation	+ (perte de contrôle immun)		+			↑ de la virémie de base	↑ à 3x >100 U/l

Complications

The following characteristics are associated with an increased risk for hepatocellular carcinoma in patients with HBV infection and are indications for surveillance with ultrasound or cross-sectional imaging every 6 months:

1. cirrhosis;
2. Asian descent plus male sex plus age older than 40 years;
3. Asian descent plus female sex plus age older than 50 years;
4. sub-Saharan African descent plus age older than 20 years;
5. persistent inflammatory activity (defined as an elevated ALT level and HBV DNA levels greater than 10,000 IU/mL for at least a few years);
6. a family history of hepatocellular carcinoma.