AIM: To assess the clinical presentation and genotypes of delta hepatitis in local population. METHODS: In this prospective study, 39 consecutive patients who were positive for HBsAg and hepatitis D virus (HDV) antibody were included. The patients were divided in two groups on the basis of presence or absence of HDV RNA and a comparative study was done. Genotype of HDV was determined in PCR positive patients. RESULTS: Overall there is male dominance, in which 34 patients out of 39 (87.2%) were male. Twenty (51%) patients were from the adjacent areas of three provinces; Sindh, Punjab and Balochistan indicating the higher prevalence of delta hepatitis in this mid region of Pakistan. Patients of all age groups were affected with delta hepatitis (median 31.5 years, range 12-75). HDV RNA was detectable in 23 patients (59%). All the HDV strains belonged to genotypeⅠ. HBV DNA was detectable only in 3 cases who were also HBeAg and HDV RNA positive. Patients with detectable HDV RNA were younger than patients with undetectable RNA; mean age 29.7 ± 12.8 years vs 36.8 ± 15.2. There were no statistically significant differences in the clinical presentation and routine biochemical profile of patients with detectable or undetectable HDV RNA. Clinical cirrhosis was present in 19 (49%) patients; 12 with detectable RNA and 7 with undetectable HDV RNA (P = 0.748). Decompensated disease was seen in eight patients; five and three respectively from each group. Four patients with undetectable RNA and two patients with detectable RNA had normal ALT and ultrasound abdomen. CONCLUSION: HDV may infect at any age, usuallyyoung adult males. GenotypeⅠ is prevalent. With time some of the patients become HDV RNA negative or asymptomatic carrier. Most of the patients have suppressed HBV DNA replication. Significant numbers of patients have cirrhosis. AIM: To assess the clinical presentation and genotypes of delta hepatitis in local population. METHODS: In this prospective study, 39 consecutive patients who were positive for HBsAg and hepatitis D virus (HDV) antibody were included. The patients were divided in two groups on the basis of presence or absence of HDV RNA and a comparative study was done. Genotype of HDV was determined in PCR positive patients. RESULTS: Overall there is male dominance, in which 34 patients out of 39 (87.2%) were male. Twenty ( 51%) patients were from the adjacent areas of three provinces; Sindh, Punjab and Balochistan indicating the higher prevalence of delta hepatitis in this mid region of Pakistan. Patients of all age groups were affected with delta hepatitis (median 31.5 years, range 12- 75). HDV RNA was detectable in 23 patients (59%). All the HDV strains belonged to genotype I. HBV DNA was detectable only in 3 cases who were also HBeAg and HDV RNA positive. Patients with detectable HDV RNA were young er than patients with undetectable RNA; mean age 29.7 ± 12.8 years vs 36.8 ± 15.2. There were no significant significant differences in the clinical presentation and routine biochemical profile of patients with detectable or undetectable HDV RNA. Clinical cirrhosis was present in 19 (49% ) patients; 12 with detectable RNA and 7 with undetectable HDV RNA (P = 0.748). Four patients with undetectable RNA and two patients with detectable RNA had normal ALT and With time some of the patients become HDV RNA negative or asymptomatic carrier. Most of the patients have suppressed HBV DNA replication. Significant numbers of patients have cirrhosis .