Molecular analysis of hepatitis B virus genomes isolated from black African patients with fulminant hepatitis B

To investigate further the possible role of mutant hepatitis B viruses in the pathogenesis of fulminant hepatitis B, the genomic sequence of hepatitis B virus isolates from 9 South African blacks with this disease, including 5 entire genomes, was analysed. Seven of the isolates were genotype A. The mutation most often reported in patients with fulminant hepatitis B, the G1896A precore stop-codon substitution, was, as expected, not present in the genotype A isolates with the exception of one in which it was accompanied by a compensatory C1858T substitution. G1896A was, however, present in the one genotype D isolate. No other precore-defective mutants were detected. The other mutation commonly found in patients with fulminant hepatitis B, the paired A1762T, G1764A substitution in the basic core promoter, was present in only one patient and G1764A in one other. The pre-surface initiation-codon mutation documented in a number of patients with fulminant hepatitis B was not found in our isolates. An 18-amino acid deletion present in the pre-surface region of one isolate has not previously been described in fulminant hepatitis B. Variations within the surface region were mainly genotype specific and not previously described. A relatively large number of mutations were present in the middle region of the core gene in those isolates without G1896A or A1762T, G1764A mutations, although the pattern was not consistent with those in published studies. Thus, as in other published series in which the entire genome of hepatitis B virus responsible for fulminant hepatitis was sequenced, we detected many mutations in different genes, but none was common to all the reported isolates.

Hepatitis B virus DNA in serum of healthy black African adults positive for hepatitis B surface antibody alone: possible association with recombination between genotypes A and D

In some patients with chronic liver disease induced by hepatitis B virus, viral DNA is known to persist in low concentration in serum after seroconversion to hepatitis B surface antibody-positivity. This phenomenon has, however, not been documented in asymptomatic black African carriers of hepatitis B virus. Using nested amplification by the polymerase chain reaction, we detected low concentrations of hepatitis B virus DNA in the serum of 6 of 23 (26%) healthy black African adults with normal liver function and with hepatitis B virus surface antibody as the only serological marker of the virus. This finding offers one explanation for the earlier observation of integrated hepatitis B virus DNA in hepatocellular carcinomas in black Africans whose serum was positive for surface antibody alone. A number of genetic changes were found in the six isolates that might be responsible for evasion of the immune response and persistence of the virus. Isolated mutations were detected in the "a" determinant of the surface gene and in the encapsidation signal. In all five isolates sequenced in the core promoter, mutations were present in the upstream regulatory region. Recombination between genotypes A and D was present in three of the isolates, including both of those in which the entire genome was sequenced. This change in genotype also overlapped the amino end of the polymerase domain and may result in sufficiently low levels of replication to allow viral persistence. Topoisomerase 1 specific trinucleotides were concentrated in the vicinity of the recombination breakpoints.

Iron deficiency in rural Ghanaian children

OBJECTIVES

To compare the prevalence of iron deficiency among Ghanaian children in different residential settings and to see whether 200mg ferrous fumerate B.P. could correct iron deficiency anaemia in observed cases of iron deficiency.

DESIGN

Prospective case-finding study using an iron-deficiency society questionnaire, laboratory data and general practice records. Crude prevalence was calculated using the hospital's mid-year estimates.

SETTING

Nkoranza in the Brong Ahafo Region of Ghana, Komfo Anokye Teaching Hospital, Kumasi, Ghana

SUBJECTS

Rural-dwelling children entering as out-patients, urban-dwelling children entering as controls and newly diagnosed iron-deficient children entering as in-patients.

MAIN OUTCOME MEASURES

Crude prevalence rates (per quinquennia) for three groups of children. Corrected deficiencies expressed as percentage after management. Age, haemoglobin, iron status, residential status, symptoms at entry and after therapy.

RESULTS

Following a 30-day administration of ferrous fumarate, the mean serum iron for the rural children increased significantly by 3.3 micromol/l representing an improved iron status of 20.0%(P<0.0001). Iron deficiency anaemia defined by serum Hb<12.0 g/dl and Fe<12.5 mmol/l decreased by 10% in the rural subjects. Comparatively, iron deficiency among the newly diagnosed anaemia group, fell by 17.6% whilst their ambulant urban counterparts employed as the control group had an iron deficiency anaemia of 0.0%.

CONCLUSION

The study clearly indicates that the-prevalence of iron deficiency anaemia among children in rural Ghana is about ten times that of the urban-dwelling children and that iron-deficiency anaemia accounts for a greater percentage of all anaemic cases among children in our hospitals. It was also shown that taking appropriate iron supplements like 200 mg of ferrous fumerate for thirty days can substantially improve the iron status of iron-deficient children.