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

Background: The current strategy for leprosy control using case detection and treatment has greatly reduced the prevalence of leprosy, but has had no demonstrable effect on interrupting transmission.

Methods: Three leprosy endemic communities in India were recruited, examined, and followed up sequentially over 2 yrs using nasal swabs and saliva collections. The nasal swabs were tested by polymerase chain reaction for the presence of M. leprae and the saliva was assayed for anti-M. leprae IgA.

Findings: Only 1.6% of 2552 nasal swabs were PCR positive, and 68% of saliva samples were positive for ML-IgA. BCG and household contact status was associated with the mucosal immune response, but not with PCR positivity. PCR positivity did not persist and most PCR positive results were in the wet season.

Interpretation: The findings contribute to our understanding of the epidemiology of M. leprae and the possible periods of greatest likelihood of exposure and transmission.

A comparative study was made of the initial and final bacterial indices (BIs) of 213 MB leprosy patients who had been administered 12-dose (Group 1/128 patients) and 24-dose (Group 2/85 patients) World Health Organization multi-drug therapy to measure the effectiveness of both treatment regimens. All patients were evaluated at the beginning of treatment, at 12 months, and again after 24 months had elapsed. Decline in BI values and average BIs at 24 months were found to be similar for both groups. Moreover, no statistical difference between the two treatment regimens was found in the frequency rate of reaction.

This study describes the circumstances under which enumerations of "lepers" were conducted in India in the late 19th century, and the ideological biases of the respective investigators and the meanings that they read into the statistics. This report focuses on the Bombay Presidency leprosy returns of 1867, examined in 1871 by Henry Vandyke Carter, and the decennial nation-wide population census of 1871-1872, 1881, and 1891, in which the leprosy-affected, among other infirm persons, were also enumerated. The evidence examined includes the investigators' reports and other published and unpublished contemporaneous documents. These censuses were undertaken at a time when the etiology of leprosy was a major controversy, but the evidence here indicates that the efforts to clarify the etiology and estimate the virulence of the disease in India by means of statistics were animated by the desire to justify and embellish pre-conceptions. Despite the claim that they were necessary for leprosy control, the censuses, for various reasons, were not utilized towards that end in India.

The authors studied 66 wild nine-banded armadillos from Brazil. The ear samples were collected and Ziehl-Neelsen or Fite-Faraco stains were performed, as well as immunostaining using polyclonal BCG antibody, to avaluate the presence of the Mycobacterium leprae. The AFB were not detected by the Ziehl-Neelsen or Fite-Faraco staining, neither immunoexpression of the BCG marker. However, many normal structures from the ears of the nine-banded armadillos, such as condrocytes, condroblasts, fibroblasts and endothelial cells, and Gram positive bacteria cocci, showed false positive reaction by the BCG marker. The authors discuss the use of the immunohistochemical studies with the polyclonal BCG antibody to identify M. leprae antigens in wild armadillos.

Background: Pure neuritic leprosy (PNL) constitutes a significant proportion of all cases in India, however, this form of disease has not been fully recognized and investigated and there is little information in the existing literature.

Objective: To study the epidemiological characteristics of PNL in India.

Materials and methods: A retrospective analysis of leprosy clinic records for the period 1993 to 2003 was undertaken. Detailed demographic profiles and clinical findings were noted from the predesigned clinic proforma. A slit-skin smear for acid-fast baclli (AFB) was done in all cases from the area of sensory loss. A skin biopsy was done from the area of sensory impairment to study histopathological changes. Further investigations such as nerve conduction velocity studies (NCV), fine needle aspiration cytology (FNAC), or nerve biopsy (superficial nerve twigs) were done if indicated in patients whenever there was difficulty in clinical diagnosis.

Results: Of the total 1542 leprosy patients seen over this period, 65 (4.2%) had PNL. Males were more commonly affected than females (2.6:1.). The majority of patients 40/65(61.5%) were aged between 15 and 35 yrs. Predominant presenting symptoms were paresthesia, pain, sensory/motor deficit, and trophic changes. A majority of the patients 39/65 (60.0%) presented with involvement of 2 or more nerves in the same extremity. Mononeuritis was seen in 26 (40%) patients. The nerves most often involved were the right ulnar nerve in the upper extremity, and the right common peroneal nerve in the lower limb. In general, the nerves of the upper extremity were more commonly involved than in the lower limbs (67 vs. 55). Motor deformities such as claw hand and foot drop were present in 13/75 (20%) and 7/65 (10.8%) patients, respectively. Slit-skin smears were negative in all patients, and skin histopathology from the area of sensory loss revealed non-specific inflammation in the dermis in a majority of patients, with perineural inflammation in a few. All patients were treated with multi-drug therapy (MDT); patients with >/=2 peripheral nerve trunk involvements were treated with WHO MDT MB regimen, while others were administered WHO MDT PB regimen. Follow-up for up to 2 yrs was available in only 32/65 (49.2%) patients, none of whom developed any skin lesions during this period.

Conclusion: PNL is a distinct subset of disease frequently seen in India. There is need to pay more attention to this form of leprosy and diagnose and treat patients earlier to prevent deformities and sequelae of nerve damage.

The objective of this study is to examine the validity of the WHO operational classification using skin smear results as the gold standard and explore the value of additional clinical signs independently and in combination with the WHO classification. Between 1985 and 2000, 5439 new untreated leprosy patients were registered at the Schieffelin Leprosy Research and Training Center, Karigiri. They were classified according to the Ridley Jopling classification as well as WHO operational classification based on the number of skin lesions. The sensitivity and specificity of the WHO operational classification tested, using skin smear results as the gold standard, was found to be 88.6% and 86.7% respectively. The Receiver Operator Characteristic (ROC) curve confirms that the best option for sensitivity and specificity is a cut off of 6 and more lesions for MB. The validity of the number of enlarged nerves and size of the largest skin lesion as independent criteria to classify patients was found to be poor. Addition of three enlarged trunk nerves to the WHO classification improved its sensitivity to 91.4%, while the specificity remained almost unchanged at 85.3%. Addition of the size of the largest skin lesion to the WHO classification reduced its validity considerably. The study concludes that the WHO recommendation of using six and more lesions for classifying a patient as MB is the best option available at the moment, and calls for further research to identify other clinical criteria that have a better validity and could be easily applied in the field.

Deep pain upon percussion of lesions over bone in tuberculoid leprosy, in spite of superficial sensory impairment, has been described as the "Tap Sign" (TS). This study was conducted to identify possible causes for this phenomenon and to determine the sensitivity and specificity of this sign in leprosy patients with lesions overlying bone. In 37/53 patients with lesions over bone, the sensitivity of the TS was 66.7% and the specificity was 100%. The positive predictive value was 100%, and the negative predictive value was 75%. The Tap Sign appears to be a useful clinical sign in diagnosis of tuberculoid and borderline tuberculoid leprosy where a lesion overlies a bone (sensitivity 66.7%). This test could be very useful to increase the clinical diagnostic yield, in the global perspective, in places where leprosy is diagnosed and treated by healthcare workers and primary care physicians without other laboratory facilities. Possible mechanisms responsible for the deep pain are discussed.

Tumor necrosis factor alpha (TNFalpha) plays a key role in orchestrating the complex events involved in inflammation and immune response. The presence of single nucleotide polymorphisms (SNPs) within the promoter region of the TNFa gene has been associated with a number of diseases. The aim of this study was to investigate the distribution of polymorphisms at positions -238 (G/A) and -308 (G/A) at the TNFalpha promoter, and its association to the outcome of different clinical forms of leprosy. Furthermore, the bacteriological index (BI) was evaluated among genotyped multibacillary (MB) patients in order to investigate the possible influence of each polymorphism on the bacterial load. This study included a total of 631 leprosy patients being 401 MB and 230 paucibacillary (PB), that was further separated according to its ethnicity (Afro- and Euro-Brazilians). The combination of SNPs in haplotypes generated three different arrangements: TNFG-G, TNFG-A and TNFA-G. In spite of the marked differences observed in the frequency of the haplotypes along the ethnic groups, no statistical differences were observed in haplotype frequencies between MB and PB patients. The BI analyses showed a lower bacteriological index among the -308 carriers, while the BI of the -238 carriers was higher. Although no significance has been achieved in this analysis regarding the influence of the polymorphisms to the development of the clinical outcome, it seems that in a different stage (among the MB patients) the polymorphisms could contribute to the degree of severity observed.