Occult HBV infection among a cohort of Nigerian adults.

OBJECTIVE: To determine markers of HBV infection and detect the presence of its occult infection in serum of a cohort of adult Nigerians. METHODOLOGY: The study involved 28 adult Nigerians with viral hepatitis (Group 1) and 28 apparently healthy adult Nigerians as controls (Group 2). Their sera were assayed for HBsAg, HBeAg, anti-HBe, anti-HBc, anti-HBs, and anti-HCV, while HBV DNA was determined in 15 patients with chronic hepatitis. Significance of differences between the patients and control subjects was assessed using Chi-square test at a 95% confidence level. RESULTS: Sero-detection of HBsAg, HBeAg, anti-HBe and anti-HBc was higher among the patients compared to the controls. HBV infection was diagnosed by HBsAg (89%) and a duo of HBsAg and anti-HBc (100%) among the patients. Similarly, eleven and four types of different patterns of HBV markers were observed among the respective groups. Anti-HBe (9.5%), anti-HBc (14.3%), and anti-HBs (9.5%) were detected among all the subjects who were sero-negative for HBsAg. HBV DNA was also detected in 86.7% of the 15 patients with chronic hepatitis, while occult HBV infection was observed in 7.2% of the patients and none (0%) of the controls, p < 0.05. Furthermore, HCV infection occurred among subjects with all the different patterns of HBV markers, except those with occult HBV infection and natural immunity to HBV. CONCLUSION: This study shows that occult HBV infection is present among Nigerian adults and determination of HBsAg, anti-HBc, anti-HBe, and HBV DNA will assist in its detection.

Faecal calprotectin: a marker of inflammation throughout the intestinal tract.

OBJECTIVE: To assess the potential of measuring the calcium-binding protein calprotectin in faeces as a method of screening for alimentary inflammation and neoplasia. SETTING: Hospital day services unit for endoscopy and faecal analysis in the clinical biochemistry department. PARTICIPANTS: Consented patients attending for routine endoscopy were requested to provide faeces. Seventeen of the initial 30 patients provided faeces before and 1 week after endoscopy. After this, 116 patients for planned endoscopy provided faeces before endoscopy. The group comprised 43 patients with upper-gastrointestinal lesions, seven patients with inflammatory bowel disease, seven patients with irritable bowel syndrome, 31 patients with colonic disorders, and 28 normal people. A final 18 patients with known inflammatory bowel disease (seven patients), gastric carcinoma (one patient), colorectal cancer (eight patients) and colorectal adenoma (two patients) had faeces analysed. METHOD: Faeces were analysed by the Nycotest PhiCal enzyme-linked immunosorbent assay (ELISA) (Nycomed, Oslo, Norway), and the final 18 patients were analysed by the newer version marketed as Calprest. RESULTS: No definite differences between pre- and post-endoscopy calprotectin were found, but it was considered preferable in the subsequent patients to analyse pre-endoscopy faeces. Upper-gastrointestinal disorders showed little difference in calprotectin levels, Barrett's oesophagus (median 6.8 mg/l), gastric ulcer (median 6.5 mg/l) or gastritis/duodenitis (median 5.2 mg/l), but these levels were all higher than the median calprotectin level of normal subjects (4.5 mg/l). The oesophageal and gastric carcinoma median was elevated significantly at 30 mg/l. Inflammatory bowel disease was also associated with marked elevation (Crohn's disease, 31.2 mg/l; ulcerative colitis, 116.2 mg/l). Colorectal polyps (median 3.7 mg/l) and adenoma (median 3.8 mg/l) showed no elevated levels in contrast to colorectal carcinoma (median 53.4 mg/l). The elevated calprotectin in inflammatory bowel disease and colorectal carcinoma combined gave a sensitivity of 81.8% and a specificity of 73.2%. CONCLUSIONS: Calprotectin levels are elevated in inflammation and cancer but are not helpful in differentiating between these disorders. In our series, calprotectin was not elevated in colonic polyps or adenomata. Calprotectin could be helpful as a screening method in a general gastroenterology population for inflammatory bowel disease and those with carcinoma, as well as assessing and monitoring disease activity in inflammatory bowel disease.