Investigation of possible zoonotic reservoirs of Indian kala-azar

Possible animal reservoirs of Indian kala-azar were investigated during a recent outbreak of the disease; dogs, Rattus rattus and Bandicoota bengalensis were examined. Microscopical and serological examinations were carried out and antileishmanial antibodies found in five out of 226 B. bengalensis.     

Detection of antigen specific circulating immune complexes in Indian kala-azar

The sera of active and treated cases of kala-azar were tested for circulating immune complexes (CIC) by antigen-specific enzyme linked immunosorbent assay (ELISA). All (100%) of proved cases had elevated CIC; 64.3% of clinically diagnosed cases and 58.8% of treated cases were also positive for CIC. A fall in the level of CIC was observed after treatment. Detection of antigen-specific CIC may be useful in monitoring the therapeutic effect and recovery.     

Risk factors for Barrett's esophagus in Indian patients with gastroesophageal reflux disease

Background and Aims: Barrett's esophagus (BE) is reported to be infrequent in Asians, with no data from India regarding its prevalence and risk factors. We investigated the frequency and risk factors of columnar mucosa with or without specialized intestinal metaplasia (SIM) in Indian patients with gastroesophageal reflux disease (GERD). Methods: A total of 278 GERD patients over 2 years underwent gastroscopy and completed a questionnaire for possible BE risk factors. Patients with columnar mucosa on endoscopy underwent four‐quadrant biopsy; BE was histologically defined as columnar mucosa with or without SIM. Patients without columnar mucosa at endoscopy were considered as controls and compared to patients with BE and those with SIM. Results: Forty‐six patients with GERD had columnar mucosa on histology (16.54%); 25 (8.99%) of these had SIM. The risk factors for BE were the presence of hiatus hernia (odds ratio [OR]: 3.14; 95% confidence interval [CI]: 1.2–8.17) and a history of eructation (OR: 2.28; CI: 1.11–4.66). The risk factors for SIM were age ≥ 45 years (OR: 2.63; CI: 1.03–6.71), hiatus hernia (OR: 3.95; CI: 1.24–12.56), and a history of eructation (OR: 3.41; CI: 1.19–9.78). Sex, severity of symptoms, dietary factors, tobacco or alcohol use, and body mass index were not associated with BE. The median circumferential segment length was 2 (1–10) cm, and the maximal length was 3 (2–11) cm in both groups. Conclusion: BE is not an uncommon finding among Indian GERD patients. Age ≥ 45 years, history of eructation, and the presence of hiatus hernia are associated with SIM.     

荒漠型黑热病流行区患病影响因素的研究

目的 探讨荒漠型黑热病流行区黑热病患病的影响因素.方法 采用1∶3匹配的病例对照研究方法,以新疆维吾尔自治区伽师县近年发病的21例黑热病患者为病例,按照1∶3的比例在同村选择性别相同、年龄相差不超过1岁、无黑热病病史及黑热病临床症状和体征,且rK39测试结果阴性的63名健康儿童作为对照,对生活习惯、居住环境和行为等因素进行问卷调查,结果用SPSS 17.0软件进行单因素分析和多因素条件Logistic回归分析.结果 单因素分析显示:畜圈与卧室的距离和近两年家庭成员或邻居有无黑热病患者两个因素在两组间存在统计学差异(P＜0.05).多因素分析显示:家畜数量、畜圈与卧室的距离及两者的交互作用具有统计学意义(P＜0.05).结论 在荒漠型黑热病流行区,家畜数量、畜圈与卧室的距离是居民患黑热病的影响因素.     

Diagnosis of Indian kala-azar by dot enzyme-linked immunosorbent assay (dot-ELISA)

Serodiagnosis of kala-azar was determined by dot-ELISA under variable conditions such as may be encountered in the field, for example, in the nature of the antigen, the preservation of antigen at different temperatures, variation in incubation temperature and so on. The test was found to be useful under field conditions, and the correlation between ELISA and dot-ELISA was significant. Dot-ELISA has definite advantages over the ELISA test, as it is easy to perform, is stable and does not require expensive equipment. The test can be used for large-scale screening of sera in sero-epidemiological studies.     

B lymphocyte population and immunoglobulins in Indian kala-azar in response to chemotherapy

The levels of immunoglobulin classes (IgG, IgM and IgA) along with B lymphocyte population size were estimated in 24 kala-azar (KA) patients and results were compared with those obtained from 30 controls. A marked increase in the level of IgG and to a lesser extent in that of IgM was noted in the sera of KA patients. But, no such difference could be noted in serum IgA level. Along with the increased levels of immunoglobulins the elevation of B lymphocyte population size was also observed. Follow-up studies during and after chemotherapy for the period of 8 months showed that clinical improvement in KA patients resulting from treatment had a positive correlation with the progressive decline in the B lymphocyte population and in the level of immunoglobulin though the latter, particularly IgG, took a longer time to return to normal.     

Leishmanin test survey in an endemic village of Indian kala-azar near Calcutta

A leishmanin test survey was carried out in a village during the declining phase of an outbreak of Indian kala-azar. One hundred and fifty of the total population of 220, including 25 clinically cured cases of kala-azar, were available for this study. Nineteen per cent (24 of 125) of the otherwise normal subjects showed delayed hypersensitivity to leishmanin antigen. The majority of these were household contacts of kala-azar patients, and the remainder came from the close neighbourhood. This may support the view that microfoci are of importance in the spread of the disease. The age-specific profile of leishmanin positivity was found to increase steadily, attaining a high level in older age groups.     

Serodiagnosis of Indian kala-azar: evaluation of IFA, ELISA and CIEP tests

The sensitivity and specificity of three serological tests viz. indirect immunofluorescent antibody test (IFAT), enzyme linked immunosorbent assay (ELISA) and counterimmunoelectrophoresis (CIEP) for the diagnosis of Indian kala-azar were evaluated. Of the 209 patients in whom Leishmania donovani parasite could be demonstrated in bone marrow, 207 (99.04 per cent) could be diagnosed with IFAT, 203 (96.6 per cent) with CIEP and 208 (99.5 per cent) with ELISA. None of these serological tests was positive in 40 healthy individuals and 10 patients each with tuberculosis, toxoplasmosis and malaria. In only one out of 10 patients with malaria ELISA alone gave false positive result. Of the 119 patients who had clinical features simulating kala-azar but were negative for Leishmania donovani in bone marrow and responded to treatment other than that for Indian Kala-azar, IFAT, CIEP and ELISA were false positive in three (2.5 per cent), nil and three (2.5 per cent) cases, respectively. The use of serodiagnostic tests like ELISA for mass screening and CIEP in less well equipped peripheral laboratories is suggested.     

Molecular typing of HLA class I and class II antigens in Indian kala-azar patients

HLA has been shown to be associated with many diseases. To find out whether host genetic factors like the HLA are involved in susceptibility to kala‐azar (visceral leishmaniasis) in India, we formulated an association study with genetically related controls. All samples were typed by PCR SSOP (sequence specific oligonucleotide probes) for HLA class I (A and B) and class II (DR) antigens. The test of association we used was the transmission disequilibrium test (TDT). No significant evidence for association with any of the three HLA loci was obtained.     

Risk factors for cholangiocarcinoma

Cholangiocarcinoma (CC) is the second most common primary hepatic malignancy after hepatocellular cancer. CC accounts for approximately 10%-25% of all hepatobiliary malignancies. There are considerable geographic and demographic variations in the incidence of CC. There are several established risk factors for CC, including parasitic infections, primary sclerosing cholangitis, biliary-duct cysts, hepatolithiasis, and toxins. Other less-established potential risk factors include inflammatory bowel disease, hepatitis C virus, hepatitis B virus, cirrhosis, diabetes, obesity, alcohol drinking, tobacco smoking, and host genetic polymorphisms. In studies where the distinction between intra- and extrahepatic CC was used, some potential risk factors seem to have a differential effect on CC, depending on the site. Therefore, the consistent use of a more refined classification would allow a better understanding of risk factors for CC.     

Risk factors for cholangiocarcinoma

Cholangiocarcinoma occurs with a varying frequency in different areas of the world. Some of the variations in incidence rates can be explained by the distribution of risk factors in different geographic regions and ethnic groups. Several accepted risk factors for cholangiocarcinoma include infestation with liver flukes, primary sclerosing cholangitis, hepatolithiasis, choledochal cysts, cirrhosis, and infusion of certain chemical agents. Approximately, 90% of patients diagnosed with cholangiocarcinoma do not have a recognized risk factor for the malignancy. The study by Ahrens et al. [16] finds that obesity and gallstones are risk factors for developing extrahepatic cholangiocarcinoma in men patients. Obesity was found to have a 'dose-effect' relationship with the strength of statistical association. No significant association was reported for tobacco or alcohol use, hepatitis, cirrhosis, diabetes, or inflammatory bowel disease. Although the author's definition of extrahepatic cholangiocarcinoma was unusual, the association of obesity with the risk of developing cholangiocarcinoma persisted for all anatomic subsites.     

Congenital kala-azar

An 11-month-old male infant was admitted to hospital with fever, pallor and hepatosplenomegaly, and was diagnosed as having kala-azar. The mother also suffered from kala-azar while carrying this baby. As the baby and the mother did not leave Delhi either during or after delivery, and the vector found in Delhi is not competent to transmit leishmaniasis, the infant could not have been infected by the bite of a sandfly. It therefore seems most likely that he was infected in utero--a rare route.     

Risk and protective factors for heavy binge alcohol use among American Indian adolescents utilizing emergency health services

Background: American Indian (AI) adolescents are disproportionately burdened by alcohol abuse and heavy binge use, often leading to problematic drinking in adulthood. However, many AI communities also have large proportions of adults who abstain from alcohol. Objective: To understand these concurrent and divergent patterns, we explored the relationship between risk and protective factors for heavy binge alcohol use among a reservation-based sample of AI adolescents. Methods: Factors at individual, peer, family, and cultural/community levels were examined using a cross-sectional case–control study design. Cases were adolescents with recent heavy binge alcohol use that resulted in necessary medical care. Controls had no lifetime history of heavy binge alcohol use. 68 cases and 55 controls were recruited from emergency health services visits. Participants were 50% male; average age 15.4 years old, range 10 to 19. Independent variables were explored using logistic regression; those statistically significant were combined into a larger multivariate model. Results: Exploratory analyses showed adolescents who were aggressive, impulsive, had deviant peers, poor family functioning or more people living at home were at greater risk for heavy binge alcohol use. Protective factors included attending school, family closeness, residential stability, social problem-solving skills, having traditional AI values and practices, and strong ethnic identity. Confirmatory analysis concluded that school attendance and residential stability reduce the probability of heavy binge alcohol use, even among those already at low risk. Conclusions: Findings deepen the understanding of AI adolescent heavy binge alcohol use and inform adolescent intervention development fostering trajectories to low-risk drinking and abstinence.     

Risk factors for dysbaric osteonecrosis

OBJECTIVES: Dysbaric osteonecrosis (DON) is a complication of ineffective decompression following exposure to high-pressure environments. This study was designed to determine risk factors for the occurrence of DON in divers. METHODS: Fifty-six male divers received skeletal examinations by radiography to assess the occurrence of DON. A questionnaire was used to obtain clinical and diving information, including diving experience and maximum diving depth. Blood samples were collected to analyse the levels of plasminogen activator inhibitor (PAI)-1, cholesterol, triglyceride, low-density lipoprotein, very low-density lipoprotein, high-density lipoprotein, apolipoprotein A1 and apolipoprotein B. RESULTS: Lesions of DON were detected in 31 of the 56 (55%) divers. Multivariate logistic regression analysis showed that high levels of PAI-1, a coagulation marker (odds ratio 4.281; P=0.0296) and great maximum diving depth (odds ratio 5.627; P=0.0231) were independent predictors of DON. CONCLUSIONS: This study has shown the presence of coagulation abnormality in divers with DON. This result suggests that a pharmacological approach incorporating the use of an anticoagulant may represent a potential strategy for the prevention of DON.