Evaluation of polymerase Chain Reaction (PCR) using hupB gene in diagnosis of tuberculous lymphadenitis in fine needle aspirates.

Backround: Although pulmonary tuberculosis(PTB) is the most common manifestation of tuberculosis, extra pulmonary tuberculosis(EPTB) has equal significance. Among the extra pulmonary manifestations, tubercular lymphadenitis (TBL) is the most common form. Objectives: To perform PCR on fine needle aspirates of lymphnode by using hupB gene as target. To compare the sensitivity and specificity of PCR with culture, cytology, serology and clinical response to therapy. Material & Methods: After processing the samples by Universal Sample Processing(USP) method,two step nested PCR was performed using two sets of primers(N1S1 & CTFR) of hupB gene. All patients were put on ATT and were followed up for two months. The response to therapy was considered as the gold standard in our study. Results: The PCR assay for hupB gene was positive in 85 patients. Of these, 82% patients showed infection with M. tuberculosis, 1% was positive for M. bovis and 2% showed co- infection with both M. tuberculosis and M. bovis. The PCR assay of hupB gene in our study showed a sensitivity of 87.4% and specificity of 66.7%. Conclusion: PCR assay for hup B gene is a rapid means of diagnosis of tubercular lymphadenitis.

Epidemiology of Ocular Infection Due to Bacteria and Fungus – A Prospective Study.

A total number of 400 cases of eye infection were studied. Among them, 250 were conjunctivitis (59.2%),120 were keratitis (53.34%) 15 were endophthalmitis (26.67%) and 15 were suffering from other infections (40%). The corneal scrapping, conjunctival swab and biopsy material ( endophthalmitis cases) was collected asceptically. The material was examined using 10% Potassium hydroxide, Gram staining and Giemsa staining. The specimens were cultured on sheeps’ blood agar, chocolate agar and sabourauds’ dextrose agar. In the bacterial cause of eye infection Staphylococcus aureus (19.13%) was the most commonly isolated organism and other pathogens isolated were Streptococcus pneumoniae (10.93%), Streptococcus pyogens (0.55%), Pseudomonas aeruginosa (4.92%), Klebsiella species(2.74%), Escherichia colli (1.10%) and Proteus mirabilis (0.55%). Among the opportunistic pathogens, Staphylococcus epidermidis, (19.13%) were the most common isolate followed by Acinetobacter species(2.74%). Alkaligenes faecalis (1.10%), Staphylococcus saprophyticus (0.55%), Staphylococcus cohnii (0.55%), Staphylococcus haemolyticus (0.55%). In the endopthalmitis patients only Pseudomonas aeruginosa (20%) and Staphylococcus epidermidis (6.67%) were isolated. In the fungal keratitis, the total fungal isolates were 32.50%. Among them Aspergillus species (56.42%) was the most common fungus isolated followed by Curvurlaria (17.95%), Cladosporium (7.70%), Candida species (5.13%), Fusarium (5.13%), Alternaria (5.13%), Penicillium (2.57%). Fungal infection is a life threatening condition, which needs early diagnosis and treatment to save the patients’ eye. Staphylococcus aureus and Staphylococcus epidermidis are still the most common isolates among the known and opportunistic pathogens in ocular infection. Pseudomonas is the most common cause of endophthalmitis. Aspergillus remains most common cause for fungal keratitis.

Evaluation of invasive and non-invasive diagnostic modalities for Helicobacter pylori infection in children.

Invasive and non invasive tests for Helicobacter pylori performed on 31 children were evaluated as diagnostic modalities. Investigations included upper gastrointestinal endoscopy and endoscopic grasp biopsy (EGB) from antrum and corpus (for rapid urease test, impression smear, histology and culture), antral brushings, serum ELISA for IgG antibodies, rapid blood test, and IgG antibodies in unstimulated saliva. Our results suggested that amongst the invasive methods brush cytology was more sensitive than histology and impression smear. Best interpretation of urease test was possible at 4 hours incubation. Culture of EGB sample constitutes the most specific way to establish the diagnosis of infection but is not easy. Hence, non-invasive modalities like serum ELISA, rapid blood test and salivary ELISA can be used in children for the detection of H pylori infection.