Oval cells and cystic structures in multiplication of M leprae.

Ten preserved biopsy suspensions from leprosy patients were inoculated in biphasic medium and incubated alternatively in refrigerator and at 37 °C. The cultures were observed every week for 3 months. The typical actinomycetoid growth appeared within 3-5 days. Microscopically, two types of cysts (unstained and dark) were seen along with oval cells. Dark cysts showed developement of irregular septae or cracks breaking the mass into irregular quadrangular pieces. Granular acid-fast material could be made out inside the cracks and around the cysts. Oval cells were seen either independently or organised around pink homogeneous material. The oval cells were stained blue or pink. Some of them showed both blue and pink shades.

Morphology of cystic structures seen in leprosy biopsy suspensions kept at cooler temperatures.

Cystic structures were seen in good numbers in biopsy suspensions obtained from leprosy patients and kept at cooler temperature. The structures were found arranged in singles, clusters or straight lines. In clusters, small round structures were seen surrounding a large spherical body. The small cystic bodies appeared empty, the medium sized bodies showed fine particles while the large ones showed spherules in and around them. It appears that the seed structure of the cycle emerges from the large spherical bodies.

Evaluation of modified lepro-agglutination as screening test for leprosy.

One hundred thirty-three leprosy sera (83 multibacillary (MB) and 50 paucibacillary (PB) cases) were screened by lepro-agglutination (LA) and M.leprae particle agglutination (MLPA) tests. Larger number of MB sera were positive by LA (86.75%) than by MLPA (45.12%) test. Thirty-seven of the 45 MB sera negative by MLPA test were positive by LA test. The reverse was true in three out of 11 MB sera. PB sera showed positivity of 16% in LA test and 24% in MLPA test. All the 55 sera from normal healthy individuals and 18 VDRL positive sera from syphilis patients were found to be negative by LA test.

Anticardiolipin antibodies in leprosy.

Eighty-four leprosy patients were studied clinically and for IgG and IgM anticardiolipin (aCL) antibodies. Following WHO criteria, 41 patients could be classified as multibacillary (MB) and 43 as paucibacillary (PB). Baseline levels of IgG and IgM antibodies were 27 +/- 4.8 GPL and 20 +/- 3.4 MPL per ml respectively. Comparing with these, 60.9% of MB and 39.5% of PB cases showed rise in IgG and IgM anticardiolipin antibodies; 19.5% of MB and 4.6% of PB sera showed rise in only IgG antibodies, while 4.8% of MB and 13.9% of PB cases showed rise only in IgM antibodies. Rise in aCL antibodies had no correlation with cardiovascular involvement, bacteriological index, reactive state and duration or regularity of treatment.

Repeated isolation of Dermatophilus-like organism from leprosy material.

An organism having actinomycetoid type of colonies has been grown repeatedly in pure culture from leprosy material using a solid medium. The isolates obtained from different biopsies, skin scrapes and mouse foot-pad harvests were found to be similar to each other in the routine taxonomical tests and had many characters common with Dermotophilus congolensis. Similar growth could be obtained from a strain of M. leprae from armadillo and also from a DOPA-positive mycobacterium isolated previously from the blood of a leprosy patient.

Observations on attempted leprosy cultures in two media.

Suspensions of skin tissue material collected from lepromatous leprosy patients and material from mouse foot-pad harvests were inoculated into two media, viz., a biphasic medium and a minimal basal medium. The cultures were incubated at 37 degrees C and 15 degrees C. Small oval (or round) cells appeared in these cultures around the tenth day along with a few cystic structures; and they increased in number later, reaching the maximum around six-seven weeks. The above cells appeared acid-fast in some cultures and some of them appeared to split into pairs of acid-fast bacilli. The cells were most often seen in the biphasic medium at 37 degrees C. The identity of these structures is not known at this stage.

Application of filter paper method for collection of blood for MLPA test.

The results of MLPA test using serum and filter paper eluate have been compared in this paper. Testing 64 patient samples at 1:32 dilution, 31 were negative by both serum and eluate, 20 were positive by both, six were positive only by serum and one was positive only eluate. In six other cases eluate gave equivocal results while serum result was clearly positive. Some eluates negative at 1:32 dilution gave weak positive agglutination at 1:16 dilution.

Specificity of IgG subclass antibodies in different clinical manifestations of leprosy.

We analysed specific IgG subclasses levels to Mycobacterium leprae sonicate extract (MSE), lipoarabinomannan B (LAM) and phenolic glycolipid I (PGL-I) in the sera of leprosy patients with different clinical manifestations. IgG2 was found to be the predominant antibody to MSE regardless of clinical manifestations, and IgG1 response was mostly seen in lepromatous patients. IgG3 reacted only rarely but IgG4 reacted relatively more in certain clinical groups such as borderline lepromatous and lepromatous with erythema nodosum leprosum (ENL) reaction. Most of the IgG subclass responses to MSE could be accounted for reactivity with LAM, suggesting that LAM is the major immunogen involved in the pathogenesis of leprosy. In contrast to LAM, PGL-I antigen showed considerably lower reactivities for IgG subclasses. An association between IgG subclass responses and clinical manifestations of leprosy was also seen. Whereas borderline lepromatous patients were found to have significantly higher levels of IgG2 and IgG4 to MSE, lepromatous patients had elevated levels of IgG1 and lower levels of IgG2. An interesting observation, however, was the significantly higher levels of IgG2 to LAM in the pure neuritic leprosy patients.

Isolation of a DOPA positive rapid growing mycobacterium from blood of a leprosy patient.

A rapid growing acid-fast organism was isolated from the blood of a borderline leprosy patient. The isolate appeared to be close to Mycobacterium cheloni group of organisms but showed globi, cigar shaped bundles and was positive for DOPA-oxidase. Catalase, iron uptake, sodium chloride tolerance, tellurite reduction, Tween 80 hydrolysis and pyridine extraction tests were also positive. The 3-days arylsulphatase test and nitrate reduction test were negative.

Significance of neither green nor red NGR bacilli in FDA-EB staining.

This Study deals with determination of viability by FDA-EB method. It has been observed that some of the bacilli do not take any colour in FDA-EB preparations. These can be called "neither green nor red" (NGR) bacilli. These non-staining bacilli should be taken into account when reporting viability by FDA-EB method.

Serum zinc/copper ratio in subtypes of leprosy and effect of oral zinc therapy on reactional states.

Serum zinc and copper levels and zinc/copper ratios were studied in 86 healthy controls, 45 cases of borderline tuberculoid (BT), 31 cases of borderline lepromatous (BL), 117 cases of lepromatous (LL) leprosy patients, 16 cases with severe erythema nodosum leprosum (ENL) reaction, and 16 cases with ENL reaction receiving oral zinc therapy. A significant reduction in serum zinc levels was noticed in all types of leprosy, the maximum decrease being seen in cases with ENL reaction. Conversely, the copper levels were significantly increased from BT to LL cases with ENL reaction in a progressive manner. A very good negative correlation (r = -0.998) was noticed between mean serum zinc and copper levels from healthy controls to active LL cases with ENL reaction. After oral zinc therapy, the serum zinc levels were significantly increased in all of the 16 LL patients with ENL reaction. In contrast, the copper levels were not decreased, indicating that oral zinc therapy can restore normal zinc levels in leprosy patients but is unable to reduce the increased copper levels.

ELISA & lepromin skin tests in household contacts of leprosy patients.

A total of 438 household contacts of leprosy patients and 228 non-contacts were studied for anti-PGL-I antibodies and cell mediated immune response to Mycobacterium leprae using ELISA and lepromin tests. The contacts showed relatively higher positivity to ELISA (29.4%) and lepromin (70.5%) as compared to non-contacts who showed 9.6 and 57 per cent positivity. In contacts as well as non-contacts the seropositivity was not found to be influenced by age and sex. However, seropositivity was higher (39.7%) in the contacts of patients with multibacillary leprosy as compared to contacts (27.7%) of patients with paucibacillary leprosy.