Study of different methods of susceptibility testing of M. tuberculosis.

This communication is on a multi-centre collaborative study carried out by New Delhi Tuberculosis (NDTB) Centre, Delhi, to compare the different methods of drug susceptibility testing (DST) of Mycobacterium tuberculosis for Streptomycin, Rifampicin, Isoniazid and Ethambutol in various accredited laboratories 40 samples (selected by simple random sampling technique) from sputum positive out-patients presenting between December 2004 and January 2005 were collected at New Delhi Tuberculosis Centre from 24 males and 16 females (age ranging from 18 to 55 years) were taken up for culture and susceptibility testing. The proportion method of DST done at NDTB Centre was taken as standard for comparing the other methods after it was found to have a good agreement with the proportion method performed at Tuberculosis Research Centre, Chennai (Kappa coefficient 0.75 to 1). All 40 sub-cultures were processed for DST by the resistance ratio and proportion methods at NDTB Centre. Also, the 40 sub-cultures were sent to Central JALMA Institute for Leprosy (JALMA), Agra that used the resistance ratio method and 25 sub-cultures were transported to National Institute of Communicable Diseases (NICD), Delhi for performing the Bactec 460TB method. The resistance ratio and proportion methods were compared both intra-laboratory (NDTB Centre) and inter-laboratory (NDTB Centre and JALMA). The sensitivity and specificity of the resistance ratio method compared to the proportion method both inter and intra-laboratory, were very high for all the drugs (except Ethambutol inter-laboratory). This was corroborated by the good agreement between the resistance ratio performed at the two centres. Bactec 460TB method, on the other hand, did not have acceptable measures of validity (sensitivity and specificity) compared to the proportion method for Streptomycin and Ethambutol. Both resistance ratio method & proportion method are comparable and either can be used for making clinical decisions. But Bactec 460 method, despite yielding early results loses out on validity.

Role of anti-depressant fluoxetine in the puva treatment of psoriasis vulgaris.

Severity of Psoriasis Vulgaris is known to be modified by psychological stress. The objective of this study was to evaluate the role of Fluoxetine in the PUVA treatment of Psoriasis. Twenty patients with progressive disease having more than thirty per cent body area involvement were included in a randomized, double blinded, placebo-controlled, age and sex matched study. All patients were on PUVA treatment; half of the patients were given Fluoxetine 20 mgms daily whereas the other ten were given placebo. Assessment was done by Psoriasis Area and Severity Index (PASI) scoring after every 5 exposures of PUVA treatment till 20 treatments. All ten patients who took Fluoxetine along with PUVA treatment showed better response and quicker remission. Fluoxetine may be used as an adjuvant in PUVA treatment of Psoriasis.

Genital lesions following bestiality.

A 48-year-old man presented with painful genital lesions with history of bestiality and abnor-mal sexual behaviour. Examination revealed multiple irregular tender ulcers and erosions, with phimosis and left sided tender inguinal adenopathy. VDRL, TPHA, HIV-ELISA were negative. He was treated with ciprofloxacin 500mg b.d. along with saline compresses with complete resolution.

Antigenic definition of plasma membrane proteins of Bacillus Calmette-Guérin: predominant activation of human T cells by low-molecular-mass integral proteins.

Mycobacterial plasma membrane proteins, in particular the detergent-soluble or 'integral' ones, comprise a class of mostly unexplored antigens capable of inducing potent activation of human T cells. Plasma membrane isolated from culture-grown Bacillus Calmette-Guérin (BCG; Indian vaccine; Danish strain) was subjected to a Triton X-114-based biphasic extraction procedure for isolation of peripheral (water-soluble) and integral proteins (PMP and IMP). A distinction between the two protein pools was evident from results of SDS-PAGE and immunoblotting using antisera raised in rabbits. An enzyme-linked immunosorbant assay with a panel of WHO-IMMYC monoclonal antibodies against various mycobacterial antigens revealed that three well-known antigens, 19 kDa, 33/36 kDa (proline rich) and 38 kDa (PstS homologue), were part of the IMP pool; and another such antigen, 14/16 kDa alpha-crystallin homologue, partly constituted the PMP pool. Apparently, antigenically distinct species of the immunomodulatory moiety lipoarabinomannan partitioned in aqueous and detergent phases. Human T-cell proliferation assays in donors comprising tuberculoid leprosy and pulmonary tuberculosis patients and healthy BCG vaccinees showed significantly greater potency of IMP over PMP and this immunodominance appeared to be directed towards CD4+ cells. IMP of < 56 kDa were resolved by 'continuous elution SDS-PAGE' into 15 fractions which, after extraction of SDS, were used in T-cell proliferation assays for the identification of immunodominant constituents. Proteins falling within three low-molecular-mass zones (all < 35 kDa) performed better than the rest, particularly a approximately 22 kDa fraction, which strongly stimulated T cells from all five donors. Partial overlap between IMP and secreted proteins, as noticed in this study, could provide clues to immunodominance of the latter. The apparent uniqueness and a high T-cell activating potency make mycobacterial IMP attractive candidates for designing future vaccines or immunotherapeutic agents.

A clinico - histopathological outcome of 4 weeks methotrexate pluse therapy in psoriasis.

A clinico-histopathological study was carried out In 50 patients of psoriasis to see clinical and histological outcome and/or correlation of weekly methotrexate pulse therapy. Clinically, results of therapy were evalutated by estimating the percentage of total body coverage with psoriasis. Prior to therapy, average involvement was 47.5% which after 4 weeks methotrexate therapy reduced to 8. 3%. A complete clearing of psoriasis occurred in 40% of patients after methotrexate therapy. The clinical response started as early as I week in most of patients. Only 2 patients failed to respond even after 4 weeks of therapy. Histopathologically in pretreatmenl biopsy, 34 showed classical psoriatic pathology while in 16 biopsy was suggestive of psoriasis but not confirmative. Histopathological examination after 4 weeks treatment showed that 41 still showed one or more histological evidence of psoriasis, although only two patients had classical, psoriatic pathology, in rest 9 patients there were complete regression. Thus, with methotrexate, clinical clearance was much faster than histopathological clearance.

Fractionation of mycobacterial integral membrane proteins by continuous elution SDS-PAGE reveals the immunodominance of low molecular weight subunits for human T cells.

Integral membrane proteins (IMP) represent a serologically distinct class of mycobacterial antigens which are potent stimulators of human T cells (Mehrotra et al., Clin Exp Immunol 1995; 102:626). The range of IMP from Mycobacterium fortuitum was resolved by continuous elution SDS-PAGE to recover 31 discrete fractions covering bands up to approximately 58 kD. The fractions, after removal of SDS, were subjected to human T cell proliferation assays for the identification of immunodominant molecule(s). A low molecular weight (<20kD) fraction was able to stimulate T cells from 11 out of 12 donors comprising mainly tuberculoid leprosy patients. The described protocol is well suited to situations where large quantities of antigenic protein mixtures must be processed in order to get the purified molecules/fractions in amounts required for immunoepidemiological studies.

Thickening of peripheral nerves in neurofibromatosis.

A 14-year-old boy presented with multiple asymptomatic swellings all over the body. Cutaneous findings were classical for neurofibromatosis. Interesting and unusual finding was generalised thickening of peripheral nerve trunks. Biopsy from thickened nerve had features of neurofibromatosis.

Favus in a non-endemic area.

A typical case of favus of scalp in a 60-year-old female, resident of a village in district Udaipur (Rajasthan) is being reported for its rarity and occurrence in non-endemic zone. Some of the nails were also involved. Fungal hyphae were demonstrated in KOH examination from scalp and nails. Culture on Sabourauds agar medium grew Trichophyton violaceum.

Methotrexate : Side effects and the role of folic acid supplementation in psoriasis - A study.

In 50 patients of psoriasis, side effects observed with methotrexate pulse were studied. Folic acid ameliorated majority of the side effects without compromising with the therapeutic efficacy of methotrexate.

A piebald family.

Piebaldism is an uncommon congenital hypomelanotic disorder characterized by a white forelock and vitiligo like amelanotic macules. We report a family with piebaldism affecting four successive generations. The disease was present in 16 members of the family.