International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association最新文献

Peripheral nerve biopsies from 4 borderline tuberculoid (BT) and 4 lepromatous (LL) patients who were on multidrug therapy were investigated by light and electron microscopic studies. The variation of diameters and distribution of myelinated and unmyelinated fibers between BT and LL patients were not significant. This study has shown significant changes in peripheral nerves and endoneural blood vessels. It was revealed that besides Schwann cells (SC), the endothelial cells (EC) of endoneural blood vessels frequently harbor M. leprae. In BT, peripheral nerves in addition to the degenerative changes of SC and presence of perineural and perivascular cuffing by mononuclear cells, the endoneurial blood vessels showed thickening of basement membrane with hypertrophy of EC leading to narrowing or complete occlusion of lumen. On the other hand, peripheral nerves of LL patients were infiltrated with large number of M. leprae shown to be present in the electron transparent zone (ETZ) of the SC. The EC of endoneurial blood vessels were found to be loaded with M. leprae, and this bacillary loaded EC was found to release M. leprae into the lumen through its ruptured membrane.

Three hundred leprosy patients were recruited to study the pattern and frequency of nail changes. Nail changes, like longitudinal ridging in finger nails, transverse striations involving both finger and toe nails etc. which occurred with similar frequency in the PB and MB patients in comparison with the control group, were excluded from the analysis. Out of a total number of 150 PB patients, 84 (56%) showed nail changes. Fifty-eight (38.6%) patients showed changes in the finger nails, with an average of 3.2 involved nails per patient. Fifty-three (35.3%) patients showed changes in the toe nails, with an average of 3.0 nails per patient. The most common change observed was longitudinal melanonychia (32.4%) in the finger nails and longitudinal ridging (46.3%) in the toe nails.In comparison, 131/150 (87.3%) MB patients showed nail changes. Finger nail changes were seen in 102 (68%) patients with an average of 5.5 nails affected per patient. Changes in toe nails were seen in 116 (77.3%) patients, with an average of 6.0 nails involved per patient. The most common nail change observed was longitudinal melanonychia in 89/523, (17%) of the total involved finger nails and subungual hyperkeratosis in 164/702, (23.4%) of the total toe nails involvement. Out of a total of 32 colony patients, 31 (96.9%) showed nail changes both in finger and toe nails with an average of 7.9 and 8.4 affected nails per patient, respectively. The most common nail change observed was rudimentary nail(s) on fingers (29%) and toes (21.1%). Among MB patients, a significantly higher number had finger nail involvement in LL group. The frequency of nail involvement for both fingers and toes was significantly greater in LL as compared to BL group of patients. The frequency of nail involvement was significantly more in patients having disease for more than 5 years and in those having trophic changes secondary to loss of sensations and impaired circulation.

The histopathological observations of Khanolkar and Iyer, that M. leprae has a predeliction for nerves, first highlighted the central role of peripheral nerves in the pathology of leprosy. It is now well recognized that nerve damage in leprosy will still continue to be an important problem in control and rehabilitation despite the presence of more efficient therapy. The multiplicity of mechanisms postulated, identified, and demonstrated in the last three decades has received little recognition from the scientific community at large. This review is therefore an attempt to collate these multiple studies on mechanisms of nerve damage into a cohesive analysis, which would facilitate the design of future studies. The objective of this review is to focus therefore only on studies which serve to illustrate mechanisms of nerve damage.

The relationship between leprosy and psoriasis has been controversial since ancient times. Based on the fundamental importance of nerve involvement in the pathogenesis of leprosy and psoriasis, it has been hypothesized that leprosy patients may be protected from developing psoriasis. There are only sporadic reports of coexistence of these two diseases as evidence of this negative association. We report a 64-year-old male patient with borderline leprosy and psoriasis. Recent advances in the elucidation of pathogenesis of both diseases have contributed to the understanding of this enigmatic relationship. Various genetic, immunological, and structural alterations in leprosy and psoriasis as discussed could be responsible for the rare co-existence of these two diseases in a given patient.

Relapse rate estimates after 2 year WHO multiple drug therapy (MDT) in multi-bacillary (MB) leprosy vary. Between 1987 and 1994, 500 MB leprosy patients completing 2 year MDT were enrolled in a prospective relapse study. The majority of patients (N = 316) were treated and followed at the physician-staffed Cebu Skin Clinic (CSC), whereas others (N = 184) received therapy from government clinics and were followed by CSC technicians in the field. Relapse definition was an increased bacteriologic index (BI) and new skin lesions, supplemented with mouse footpad inoculations. Through 2002, follow-up was 5368 person-years, with a mean of 10.8 years per patient. The absolute relapse rate was 3% (15/498; 0.28/100 person-years), with a cumulative risk estimate of 3.9% at 15 yrs. For a subset of 217 patients followed for >or=12 yrs or until relapse, relapses occurred in 9% (13/142) attending the CSC, versus 3% (2/75) assessed in the field (p = 0.09). The rate for patients followed at CSC for >or=12 yrs and a pre-treatment BI >or=2.7+ was 13% (13/98). All relapses were BL or LL, with pre-treatment BI's of >or=2.7+. Relapses occurred long after completion of therapy, between 3 and 11 yrs from the midpoint of the examination without relapse to detection, or between 6 to 13 yrs to the actual year of detection, 7 occurring at >or=10 yrs. Lesion material from all relapses contained M. leprae that was rifampin and clofazimine sensitive, whereas 3 showed partial or full dapsone resistance. [Follow-up rigor and time], medical expertise, and pre-treatment bacterial load influence relapse rates after 2 yr MDT.

Mycobacteria leprae isolates obtained from 37 referral relapse cases of leprosy (37 skin and 10 nerve biopsy samples) received during the years 1994-2001, were tested for viability and drug sensitivity in the mouse footpad. A significant M. leprae yield in the footpads of control mice was obtained, with 32/47 (68%) isolates (from 26 cases) thus confirming viability. Of the 28 isolates successfully drug tested, 6 (21%) were resistant to one or more drugs. All except one, were multidrug treated cases (5/24 = 21%). One of the isolates was resistant to all three drugs, i.e., dapsone (di-aminodiphenyl sulphone, DDS), rifampin (RFP), and clofazimine (CLF). Two were resistant to two drugs, i.e., DDS and RFP, and each of the others were mono resistant to DDS, RFP, or CLF. Notably, one of the isolates that showed combined resistance to DDS and RFP was derived from a borderline tuberculoid case. Also, in one case skin and nerve showed that discordance viz: M. leprae derived from skin were resistant to RFP, while those derived from nerve tested sensitive to all three drugs, indicating tissue related difference.

Objective: The primary objective of our research was to explore help-seeking behavior in the context of knowledge, attitude, and practice as factors contributing to delay in presentation in leprosy. The secondary objective was to demonstrate the value of basic qualitative research methods in this context.

Methodology: Fieldwork was based at the Hospital Mennonita Km 81, the referral center for leprosy services in Paraguay. We adopted exclusively qualitative methods for fieldwork, effectively carrying out a rapid assessment of factors contributing to delay. We relied on multiple sources of information and the use of multiple methods to ensure the validity of our findings.

Results: Our findings linked delay in presentation to traditional beliefs, lack of awareness of the early symptoms of leprosy, stigma, seeking help from natural healers, and to interactions with the health services. Traditional beliefs diminish the importance of the early symptoms of leprosy. Stigma has an impact on decisions to seek help. Natural healers have maintained their traditional status in society; their preferred treatments for leprosy are ineffective. Only rarely do natural healers refer to the health services. Once presented to the health services, some individuals affected by leprosy experienced lengthy delays in diagnosis and start of treatment.

Discussion: To address the traditional values of a society and provide effective public health initiatives is a clearly a major challenge for program organizers and for health education. Increased awareness of leprosy and sensitivity to its social consequences among health service practitioners is a further priority.

In this study, clinically all forms of lesions like macules, plaques, and nodules were found in all the "relatively spared zones," except groins. Histopathology confirmed that the disease process was established and the acid-fast bacilli were not present as a part of bacteremic settlement. Hence, it appears that practically no area on the surface of skin is immune to invasion by M. leprae. However, as the incidence of lesions and AFB in these regions is relatively less, especially over axilla and groin, these areas can be considered as relatively spared zones but not completely resistant to development of lesions of leprosy.