Urinary iodine status and thyroid dysfunction: a Bangladesh perspective.

Iodine deficiency is endemic in Bangladesh. Compulsory iodization of table salt was introduced since 1993 to prevent and improve thyroid disorders in the country. Urinary iodine status, thyroid function and antithyroid antibodies were studied in 397 newly diagnosed thyroid patients and 94 age-sex matched controls. Among thyroid patients, 96 were hyperthyroid, 185 euthyroid and 116 hypothyroid. Mean and median urinary iodine were higher (p=0.075) in thyroid patients (26.13+/-0.91 and 23.03) than controls (22.65+/-1.47 and 18.59); in hyperthyroid and euthyroid than hypothyroid (p=0.020); in multinodular (28.08+/-2.80 and 26.94) and diffuse (27.35+/-1.19 and 26.71) goitre than uninodular (23.91+/-2.37 and 19.14) and nongoitrous (NG, 21.5+/-2.05 and 18.27) (p=0.098) patients but no sex difference (p=0.466). Antimicrosomal (26.7%) and antithyroglobulin (34%) antibodies were more frequently positive among thyroid patients than controls (6.4% and 12.8% respectively) (p=0.00002 and p=0.00005 respectively). Antibody positivity was higher in diffuse (82/228) and multinodular (20/47) goitre than nongoitrous (20/56) and uninodular (13/66) goitre (p=0.046) as well as in hypothyroid (55.2%) and hyperthyroid (36.5%) than euthyroid (19.5%) patients (P<0.001). Urinary iodine correlated neither with antimicrosomal (thyroid patients: p=0.597 and control: p=0.112) nor with antithyroglobulin (thyroid patients: p=0.388 and control: p=0.195) antibody. Thyroid autoimmunity and dysfunction seems common; and interaction of salt iodization with iodine status and thyroid disorders may be important in Bangladesh.

PCR can help early diagnosis of pulmonary tuberculosis.

One hundred and fifty-one patients, clinically suspected for pulmonary tuberculosis (age: 31 +/- 13 years, male/female: 112/39), were investigated to evaluate the diagnostic potential of polymerase chain reaction (PCR) based detection of the Mycobacterium tuberculosis complex in sputum. The diagnostic efficacy of PCR was compared with culture of Mycobacterium tuberculosis on egg-based Lowenstein-Jensen modified medium. PCR detected 71.5% (108/151), whereas culture detected 66.2% (100/151) of the clinically suspected patients. There was a significant association between the results of PCR and culture (chi2 = 59.524, p < 0.001). However, 23.2% (35/151) samples were found negative in both culture and PCR. Considering culture as the gold standard, the sensitivity of the PCR was 92%. and its specificity 70%. This lower apparent specificity may be due to the higher sensitivity of PCR.

Predominance of the DEN-3 genotype during the recent dengue outbreak in Bangladesh.

A recent outbreak of dengue in Bangladesh was marked by many fatal complications. As clinical virulence varies among the genotypes of dengue virus, a study was conducted to investigate the molecular genotypes of dengue in Bangladesh. Reverse transcription polymerase chain reaction was used to determine viral genotypes using oligonucleotide generic primers that produce a 511 bp product. The resulting product was typed by nested PCR with strain-specific primers, yielding 482 (DEN-1), 119 (DEN-2), 290 (DEN-3) and 392 (DEN-4), visualized on UV transilluminator after electrophoresis on 2% agarose gel stained with ethidium bromide. Of 45 clinically diagnosed dengue patients (mean age 28 years; male/female 30/15), 19 (42.2%) had detectable viral RNA in their blood. However, during the first 5 days of fever in 30 patients, the frequency was 60% (18/30), implying that the sooner serum is drawn after the fever, the greater the chances of detecting viral RNA. DEN-3 was detected in all except 2 patients who were infected with DEN-2. DEN-2 (two cases) and DEN-4 (one case) were present as co-infections with DEN-3. All of the patients presented with fever, anorexia and vomiting; many had headache and general body ache; a few had a rash. About a quarter had suffered episodes of bleeding, while ascites, pleural effusion and CNS symptoms were found in a few patients Patients positive for viral RNA were also positive for anti-dengue IgM (p=0.007) in subsequent sampling. The study suggests the predominance of DEN-3 infection with occasional co-infection with other types, during the recent outbreak of dengue in Bangladesh.

Genetic background of diabetic and nondiabetic sibs in young Bangladeshis.

The prevalence of diabetes mellitus in the young is higher in Bangladesh like other Asian developing nations. Albeit, undernutrition has been shown to be associated with diabetes in the young, not all such individuals are diabetic. Diabetes Mellitus is a multigenic disease. In IDDM, DR3/4 heterozygotes were shown to have a greatly increased risk of developing the disease, suggesting the concept of genetic factor(s) being involved in the development of diabetes. Therefore, this study was undertaken to determine the distribution of HLA class II alleles (DRB) and to identify the HLA associated risk for developing diabetes mellitus in the young Bangladeshis. A total of fifty individuals were investigated. Half of them (n=25) were diabetic patients, registered in BIRDEM and half the participants were their non-diabetic sibs. A genomic DNA PCR and Enzyme Linked Probe Hybridization Assay (ELPHA, Bio-test, Germany) was used to determine HLA class II alleles (DRB1, DRB 3, 4, 5) by in vitro amplification of DRB gene. Among all the sero-equivalent antigens found in the study subjects, the prevalence of DR15 (DR2) was overrepresented, both in the diabetic subjects and in their non-diabetic sibs. Moreover, compared with the non-diabetic group the diabetic patients showed higher frequency of DR15 alleles (39 and 25%) though the difference was not significant (chisq. 1.7, p>0.05). Next to DR15, DR4 was the most prevalent HLA-DRB gene found in the study population. Interestingly, the frequency of DR4 was higher in the diabetic than in the non-diabetic group (20 vs. 14%). The study showed that the DR15 and DR4 were the most prevalent in the study population. Moreover, DR7 though not very significant, was higher in non-diabetic compared to their diabetic sibs. Comparison between the diabetic and non-diabetic sibs could have been interesting and significant but we could not confirm our findings, possibly, due to small sample size. A study in a larger paired sample of unrelated population is also needed to substantiate our findings, and also to prove the susceptibility or resistant haplotype in the young diabetic subjects.