Indian Pediatrics - Editorial

Letters to the Editor

Indian Pediatrics 2003; 40:278

HBV Related Chronic Liver Disease

We want to raise some pertinent issues related to the article by Guptan et al.(1). Firstly, authors have used interferon(IFN) in a dose of 50,000 to 75,000 IU/Kg body weight. They have not given the reference, where from they have got this dose. In children, dose of interferon is calculated on the basis of body surface area and not on body weight. The dose varies from 3 to 10 MIU/m2(2,3). Calculation of drug dose on the basis of weight may be falacious. Moreover, most of the chronic liver disease patients are malnourished or edema-tous which further compounds the problem of dose calculation on the basis of body weight. IFN is a very costly drug with lot of side effects. Hence, appropriate dosing is very important.

Secondly, authors have mentioned that the age ranged between 9 to 12 years with a mean of 8.6 ± 2.4 years. How is it possible to have a mean age of 8.6 years when age range starts from 9 years.

Thirdly, it is a known fact that many patients respond or seroconvert on follow up after IFN treatment. In a study of 107 children, Bortolotti et al.(4) demonstrated that initial response to IFN treatment was just 15% but cumulative HBeAg clearance rate at 5 years was 60%. Similarly, Lin et al.(3) in a study of 101 patients observed that initial response was 42% with IFN treatment but it rose to 75% on follow up. In this study(1) response to IFN treatment is low because of two facts: (a) half of the cases are vertically transmitted HBV where response to IFN is poor and (b) the duration of follow up (mean 16 months only) is limited.

Vertically acquired HBV goes through a different kind of life cycle than horizontally acquired HBV(5). In vertically acquired HBV, the "immune tolerance" stage (asymptomatic with normal liver function and replicating HBV) lasts for several decades. IFN does not work at this stage as there is no host immune response against HBV. In this study also many of the vertically acquired HBV children probably had normal transaminases, indicated by very high SD value. Moreover, liver biopsy was not done in 6 cases and authors have not mentioned who were these 6 cases (Group I or Group II). Obviously some of the vertically acquired (Group I) children did not merit IFN therapy. Ultimate results of IFN treatment is being skewed by this group. Another message of this study should have been that the vertically transmitted HBV in children should not be treated with IFN unless or until they show evidence of liver damage in terms of raised liver enzymes and histological changes.

Ujjal Poddar,
B.R. Thapa,
Department of Gastroenterology,
PGIMER, Chandigarh 160 012.
E-mail: [email protected]

REFERENCES

1. Guptan RC, Thakur V, Malhotra V, Sarin SK, Recombinant interferon therapy in Indian children with HBV related chronic liver disease. Indian Pediatr 2002; 39: 462-467.

2. Lee-Ng V, Balistreri WF. Hepatitis B: Clinical perspectives in pediatrics. Clin Liver Dis 1999; 3: 267-290.

3. Lin S, Sheen I, Chien R, Chu C, Liaw Y. Long-term beneficial effect of interferon therapy in patients with chronic hepatitis B virus infection. Hepatology 1999; 29: 971-975.

4. Bortolotti F, Jara P, Barbera C, Gregorio GV, Vegnente A, Zancan L, et al. Long-term effect of alpha interferon in children with chronic hepatitis B. Gut 2000; 46: 715-718.

5. Lee WM, Hepatitis B virus infection. NEJM 1997; 337: 1733-1744.