Nooruddin Ahmad

Prospective Case-Control Study of the Association between Common Enteric Protozoal Parasites and Diarrhea in Bangladesh

BACKGROUND The parasitic causes of diarrhea have historically been identified by use of microscopy; however, the use of this technique does not allow one to distinguish between subspecies or genotypes of parasites. Our objective was to determine, by use of modern diagnostic methods, the proportion of diarrhea cases in Bangladesh attributable to Cryptosporidium hominis, Cryptosporidium parvum, Entamoeba histolytica, and Giardia lamblia assemblages A and B. METHODS A prospective case-control study was performed involving 3646 case patients (both children and adults) who presented with diarrhea to the Dhaka hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, and 2575 control subjects with asymptomatic infection. Parasitic infection was detected by use of a stool parasite antigen test, and the parasite load and the species and/or genotypes were determined by use of polymerase chain reaction (PCR). RESULTS Cryptosporidium species and E. histolytica were more prevalent in patients with acute diarrhea than in healthy control subjects, for all ages (2.1% vs. 1.4%; P = .039) and, specifically, for those 0-12 months of age (2.2% vs. 0.4%; P = .009). G. lamblia assemblage A was also more prevalent in case patients with diarrhea than in healthy control subjects (20% vs. 5%; P = .001). For case patients with diarrhea, the parasite load in feces, as measured by quantitative real-time PCR cycle threshold, was not higher that that for control subjects with asymptomatic infection. Case patients with diarrhea and cryptosporidiosis were less likely to have abdominal pain, compared with control subjects (15% vs. 37%; P = .001); case patients with amebiasis more likely to have visible blood in stool, compared with control subjects (8% vs. 1.6%; P = .001); and case patients with giardiasis more likely to be dehydrated, compared with control subjects (81% vs. 71%; P = .001). CONCLUSION E. histolytica, C. hominis, C. parvum, and G. lamblia assemblage A infections are important causes of diarrheal illness in Bangladesh.

Frequent coinfection with hepatitis B virus strains of distinct genotypes detected by hybridization with type-specific probes immobilized on a solid-phase support

A genotype-specific probes assay (GSPA) was developed for distinguishing the seven genotypes (A-G) of hepatitis B virus (HBV). Nucleotide (nt) sequences corresponding to preS1 region were amplified by PCR with a primer labeled with biotin, and delivered to eight wells on which complementary sequences specific to one or other genotype had been immobilized. Thereafter, hybridization of HBV DNA sequences amplified from the test serum was detected by colorimetry. When 256 sera from HBV carriers in Bangladesh, Cameroon, Japan, South Africa, USA and Uzbekistan were subjected to GSPA, genotypes were concordant with those of ELISA with monoclonal antibodies to epitopes on preS2-region products in 242 (94.6%) of them; 8 sera (3.1%) were not genotypeable by either method. Cloning analysis confirmed the presence of two distinct HBV genotypes in the seven selected sera with coinfection. There were 7 (2.7%) sera with discordant genotyping results between GSPA and ELISA. When HBV DNA clones propagated from these sera were sequenced and analyzed phylogenetically, the genotypes determined by GSPA were verified. Coinfection with HBV strains of two distinct genotypes was identified by GSPA in 28 (10.9%) sera, while it was suggested by ELISA in only 2 (0.8%) sera. The GSPA method would be particularly useful for detecting the coinfection with distinct HBV genotypes of any clinical relevance, which seems to be more frequent than reported previously.

Insulin resistance in development and progression of nonalcoholic fatty liver disease

Although insulin resistance (IR) is strongly associated with nonalcoholic fatty liver disease (NAFLD), the association of IR and NAFLD is not universal and correlation between IR and severity of NAFLD is still controversial. In this review, we summarize recent evidence that partially dissociates insulin resistance from NAFLD. It has also been reported that single-nucleotide polymorphisms in the diacylglycerol acyltransferase gene, rather than IR, account for the variability in liver fat content. Polymorphisms of the patatin-like phospholipase 3 gene have also been reported to be associated with NAFLD without metabolic syndrome, which suggests that genetic conditions that promote the development of fatty changes in the liver may occur independently of IR. Moreover, environmental factors such as nutrition and physical activity as well as small intestinal bacterial overgrowth have been linked to the pathogenesis of NAFLD, although some of the data are conflicting. Therefore, findings from both genetically engineered animal models and humans with genetic conditions, as well as recent studies that have explored the role of environmental factors, have confirmed the view that NAFLD is a polygenic disease process caused by both genetic and environmental factors. Therefore, IR is not the sole predictor of the pathogenesis of NAFLD.

Evaluation of normal or minimally elevated alanine transaminase, age and DNA level in predicting liver histological changes in chronic hepatitis B

Background: Serum alanine transaminase (ALT), hepatitis B virus (HBV) DNA level and age are used in the evaluation of chronic hepatitis B (CHB).

Seroepidemiology of HBV and HCV in Bangladesh

Abstract Virus related liver diseases are important causes of morbidity in Bangladesh. We have reviewed the data of different authors to assess the magnitude of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in this country. HBV accounts for 35% acute viral hepatitis, 40.5% chronic liver disease, 36.5% hepatocellular carcinoma and 29.1% cases of post transfusion hepatitis. HCV accounts for 3.5% acute viral hepatitis, 24.1% chronic liver disease, 9.6% hepatocellular carcinoma and 6.8% cases of post transfusion hepatitis. Blood donors are not routinely screened for HBsAG except in a few selected centers. Twenty-nine percent of professional blood donors and 2.4% of voluntary blood donors are HBsAG carriers. Anti-HCV was found in 1.2% of professional blood donors and in no voluntary donors. HBsAG is positive in 7.5% of healthy adult jobseekers. In our series of acute viral hepatitis, there was no history suggestive of parenteral route of infection in 60% cases of HBV and 54% cases of HCV. In conclusion, HBV is the main aetiological factor for chronic liver disease in Bangladesh.

Natural course of fulminant hepatic failure: The scenario in Bangladesh and the differences from the west

Background/Aim: Fulminant hepatic failure (FHF) is a devastating complication of acute viral hepatitis, leading to death in most cases. The etiology and predictors of outcome differ according to the geographical region. This study was conducted with the aim of evaluating the etiology, complications, and outcome of FHF in Bangladesh. Patients and Methods: In this prospective study, we included 67 consecutive cases of FHF presenting to the Department of Hepatology, Bangabandhu Sheikh Mujib Medical University, Dhaka, between November 2003 and May 2008. Thirty-nine of the patients were male and 28 were female. Data was analyzed using SPSS, version 13.0. Results: The mean age of the subjects was 31.9 ± 11.7 years. Hepatitis E virus (HEV) was the commonest etiological factor for FHF (50 cases, 74.6%); of the 50 cases with HEV infection, 43 (64.2%) were not coinfected with any other virus, four cases were Hepatitis B virus (HBV) carriers, and three had coinfection with hepatitis A virus (HAV). HBV was the cause of FHF in nine (13.4%) patients. HCV, paracetamol, and alcohol were not responsible for any of the cases. Most of the patients (57 patients, 85%) developed FHF within 2 weeks of the onset of jaundice. Of the 67 patients, 49 (73.1%) died. Cerebral edema was the single most common cause of death (48 patients, 71.6%). Other complications were renal failure (23 patients, 34.3%), sepsis (15 patients, 22.4%), electrolyte imbalance (12 patients 17.9%), and bleeding tendency (7 patients, 10.4%). Occurrence of cerebral edema, longer prothrombin time, higher grade of encephalopathy, and longer jaundice-to-encephalopathy interval had significant negative influence on outcome. Conclusions: The etiology of FHF in Bangladesh is different from that in the West. Prolongation of prothrombin time and occurrence of cerebral edema are predictors of the worst prognosis.

Characteristics of treatment naive chronic hepatitis B in Bangladesh: Younger populations are more affected; HBeAg-negatives are more advanced

Background/Aim: Bangladesh is a densely populated country with intermediate endemicity for chronic hepatitis B (CHB). The aim of the present study was to evaluate the biochemical, virological and histological character of CHB patients and to examine the relationship between these indices. Materials and Methods: One thousand and twenty-two patients of CHB fulfilled our inclusion criteria. Inclusion criteria were (1) HBsAg positive for at least 6 months, (2) HBeAg-positive or negative and (3) hepatitis B virus (HBV) DNA positive. Patients with detectable antibodies to human immunodeficiency virus (HIV), hepatitis Delta virus (HDV) or hepatitis C virus (HCV), with previous antiviral treatment, overt cirrhosis and hepatocellular carcinoma, were excluded. Of these, 191 patients were randomly selected for liver biopsy and were evaluated for analysis. Results: In the 191 patients, male to female ratio was 4.6:1; age distribution was 26.5 ± 8.5 (mean ± standard deviation) years. One hundred and seventy-eight (93.2%) patients were under 40 years. Sixty-eight (35.6%) patients were HBeAg-negative, had less DNA load, and were significantly older, more fibrotic and cirrhotic (P < 0.001). Correlation was not found between DNA level and histological activity. Histological activity was not correlated with ALT level in HBeAg-positive patients (P < 0.001). Conclusion: CHB affects the younger population in Bangladesh. HBeAg-positive CHB was associated with more fibrosis and cirrhosis. Serum HBV DNA levels do not correlate with the severity of histological lesions in all patients. Evaluation by liver biopsy remains gold standard for taking decision of treatment.

Effect of sitagliptin on hepatic histological activity and fibrosis of nonalcoholic steatohepatitis patients: a 1-year randomized control trial

Background/purpose Dipeptidyl peptidase 4 (DPP-4) expression is directly associated with hepatic lipogenesis and liver injury in nonalcoholic steatohepatitis (NASH). This study has been designed to elucidate the histological improvement of NASH with the DPP-4 inhibitor sitagliptin. Materials and methods In this open-label randomized control trial, paired liver biopsy was taken from 40 NASH patients. Sitagliptin 100 mg was given once daily to the SL group and no sitagliptin was given to the L group for 1 year. Patients from both groups were encouraged to exercise moderately and advised to avoid saturated fat, excessive sugar, soft drinks, fast food, and refined carbohydrates to reduce weight. Results Steatosis improved in the SL group (from 2.3±0.6 to 1.2±0.8; P=0.000) and the L group (from 2.1±0.6 to 1.6±0.9; P=0.008), ballooning decreased from 1.8±0.6 to 1.3±06 (P=0.002) in the SL group, but not in the L group. Nonalcoholic fatty liver disease activity score (NAS) attenuated in both groups: the SL group (from 5.8±0.9 to 3.9±1.4; P=0.000) and the L group (from 5.3±0.6 to 4.6±1.2; P=0.009). NAS improvement was much higher in the SL group (1.9±1.4) than in the L group (0.7±1.1) (P=0.006), with NAS improving by ≥2 in 13 patients from the SL group and five patients from the L group (P=0.01). Improvement was irrespective of diabetes. Regression analysis explored that sitagliptin had odds of 6.38 and weight reduction had odds of 4.51 for NAS reduction. Conclusion Sitagliptin 100 mg once daily for 1 year ameliorates NAS by improving steatosis and ballooning, irrespective of diabetes. Sitagliptin has stronger efficacy than that of weight reduction.

Effect of pentoxifylline on histological activity and fibrosis of nonalcoholic steatohepatitis patients: A one year randomized control trial

Abstract Background and Objectives To observe the effect of Pentoxifylline for 1 year on hepatic histological activity and fibrosis of nonalcoholic steatohepatitis (NASH). Materials and Methods A single center, open label Randomized Control Trial. Patients were included if they had ultrasonographic evidence of fatty liver and nonalcoholic fatty liver disease activity score (NAS) ≥ 5 on liver histology. A total of 35 patients were selected; 25 of PL (Experimental) group and 10 of L (Control) group. PL group received 400 mg pentoxifylline thrice daily along with lifestyle modification and there was only lifestyle modification for the L group. After one year, NAS and fibrosis was compared in both groups. Results In PL group, NAS improved 2.10 ± 1.07; whereas in L group, NAS was 0.90 ± 0.99 (P = 0.006). As per the protocol analysis, NAS ≥ 2 improved in 15/20 (75%) in PL group and in 3/10 (30%) in L group (P = 0.018). In PL group, the individual component of NAS, steatosis improved from 2.30 ± 0.66 to 0.95 ± 0.76 (P = 0.000), lobular inflammation from 1.65 ± 0.59 to 1.05 ± 0.51 (P = 0.002) and hepatocyte ballooning from 1.50 ± 0.51 to 1.30 ± 0.57 (P = 0.258). In L group, steatosis improved from 2.30 ± 0.68 to 1.40 ± 1.08 (P = 0.01), lobular inflammation and hepatocyte ballooning did not improve. The fibrosis score did not improve in any group. In PL group, NAS improved significantly (P = 0.027; OR=22.76, CI=1.43-362.40) independent of weight reduction. Conclusion Pentoxifylline for 1 year improves the hepatic histological activity but not fibrosis of NASH patients.

Prevalence and risk factors of non‐alcoholic fatty liver disease in Bangladesh

Non‐alcoholic fatty liver disease (NAFLD) is a significant cause of hepatic dysfunction and liver‐related mortality. As there is a lack of population‐based prevalence data in a representative sample of general population, we aimed to estimate the prevalence and risk factors of NAFLD in Bangladesh.