Leprosy: diagnosis and management in a developed setting

Leprosy rash precipitated by immunotherapy for suspected inflammatory neuropathy

Leprosy is a chronic granulomatous infection caused by Mycobacterium leprae complex, causing skin and nerve lesions with potential for permanent disability. Leprosy can be overlooked in Western settings, as it is more prevalent in low-income and middle-income countries. We describe a 38-year-old woman with a 4-year history of progressive numbness of the left hand incorrectly diagnosed as multifocal acquired demyelinating sensory and motor neuropathy on the basis of clinical and neurophysiological findings. Treatment with empirical weekly corticosteroid followed by intravenous immunoglobulin resulted in the sudden development of a widespread rash; we then diagnosed borderline lepromatous leprosy on skin biopsy. We postulate that the immune treatments induced a temporary state of immune tolerance followed by a rebound of a T cell-mediated immune response resulting in a type 1 immunological response.

The protective role of tissue-resident interleukin 17A-producing gamma delta T cells in Mycobacterium leprae infection

Mycobacterium leprae is a kind of disease-causing bacteria and results in leprosy in human. Gamma delta (γδ) T cell is a T-cell subset that is presented in both human dermis and epidermis. These cells bridge innate and adaptive immune responses and play critical roles in regulating anti-microbial defense, wound healing, and skin inflammation. Here, we investigated skin resident γδ T cells in patients with leprosy. Our data showed that γδ T cells significantly accumulated in skin lesions of leprosy patients with tuberculoid (TT) form. IL-23 can predominantly stimulate dermal γδ T cells to produce interleukin 17 (IL-17), a cytokine which may lead to disease protection. These γδ T cells expressed a specific set of surface molecules, and majority of these cells were Vδ1+. Also, IL-23 can stimulate the expansion of dermal γδ T cells expansion. Moreover, our results revealed that the transcription factor RORγt was responsible for IL-17A expression in leprosy lesion. Therefore, these data indicated that IL-23-responsive dermal γδ T cells were the major resource of IL-17A production in the skin and could be a potential target in the treatment of leprosy.

Delayed detection of leprosy cases: A systematic review of healthcare-related factors

Background

In new leprosy cases, grade 2 disability (G2D) is still a public health burden worldwide. It is often associated with the delayed leprosy diagnoses that healthcare systems should play a crucial role in preventing. The aim of this systematic review was to identify healthcare factors related to delays in case detection in leprosy.

Methods

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) was used as a guideline in this research. The study protocol was registered in the PROSPERO (International Prospective Register of Systematic Reviews) with reference code CRD42020189274. Data was collected from five electronic databases: Embase, Medline All Ovid, Web of Science, Cochrane CENTRAL, and the WHO Global Health Library.

Results

After applying the selection criteria for original empirical studies, and after removing duplicates, we included 20 papers from 4313 records. They had been conducted in ten countries and published between January 1, 2000, and January 31, 2021. We identified three categories of healthcare factors related to delayed case. 1) Structural factors, such as i) financial and logistic issues, and geographical circumstances (which we classified as barriers); ii) Health service organization and management including the level of decentralization (classified as facilitators). 2) Health service factors, such as problems or shortages involving referral centers, healthcare personnel, and case-detection methods. 3) Intermediate factors, such as misdiagnosis, higher numbers of consultations before diagnosis, and inappropriate healthcare services visited by people with leprosy.

Conclusions

Delays in leprosy case detection are due mainly to misdiagnosis. It is crucial to improve the training and capacity of healthcare staff. To avoid misdiagnosis and reduce detection delays, national leprosy control programs should ensure the sustainability of leprosy control within integrated health services.

New leprosy patients diagnosed with visible physical deformities represent a significant disease burden that also poses an important public health challenge. The physical deformities often result from long delays in case detection. Greater insight into the healthcare factors that contribute to such delays will support the development of effective prevention programs. We therefore reviewed all studies on the healthcare factors related to case-detection delay that had been published between January 1, 2000, and January 31, 2021. Twenty studies were included in our analysis. We found that misdiagnosis was a core healthcare factor related to delays. Other common factors included inappropriate health services, a high number of consultations before diagnosis; and a lack of referral centers, healthcare personnel, and case-detection methods. Detection delay was further influenced by geographical circumstances, financial and logistic issues, and health-service organization and management including the level of the decentralization of healthcare programs. Because delays in leprosy case detection are due mainly to misdiagnosis, we recommend to improve the training and capacity of healthcare staff. To avoid misdiagnosis and reduce detection delays, national leprosy control programs should ensure the sustainability of leprosy control within integrated health services.

Modern Solutions for Ancient Pathogens: Direct Pathogen Sequencing for Diagnosis of Lepromatous Leprosy and Cerebral Coenurosis

Microbes unculturable in vitro remain diagnostically challenging, dependent historically on clinical findings, histology, or targeted molecular detection. We applied whole-genome sequencing directly from tissue to diagnose infections with mycobacteria (leprosy) and parasites (coenurosis). Direct pathogen DNA sequencing provides flexible solutions to diagnosis of difficult pathogens in diverse contexts.

Endoneural abscess of common popliteal nerve as first clinical manifestation of leprosy: the first reported case in history in a low-incidence country

A migrant from Palestine came to our attention for weakness of dorsiflexion of the left foot and hypoesthesia of the homolateral common peroneal nerve territory. Skin biopsies from skin lesions in the hypoesthetic area were not diagnostic. Radiological investigation showed focal nerve enlargement with a possible focal lesion. At this time, and given the uncertainty of the diagnosis, we had to choose between medical therapy with steroid and a surgical exploration of the nerve. We decided for the latter option. Intraoperatively, we found a focal round enlargement of the nerve. Epineurotomy was performed at that level, revealing a round caseous granulomatous mass that was excised. Microbiological examination revealed presence of Mycobacterium Leprae allowing diagnosis of leprosy. Medical therapy was then started, leading to resolution of clinical symptoms. Endoneural lepromatous abscesses are uncommon lesions that should be suspected in patients presenting with peripheral nerve dysfunction with anamnesis of travel in leprosy endemic regions or contacts with people from endemic regions with or even without skin lesions. Detection of endoneural abscesses is of critical importance because prompt surgical excision in conjunction with medical therapy leads to improvement of symptoms and permits correct diagnosis. In times of large human migrations from leprosy endemic areas, knowledge of this uncommon presentation of leprosy and its management will help lead to the best management of these patients.

Reprogramming of Small Noncoding RNA Populations in Peripheral Blood Reveals Host Biomarkers for Latent and Active Mycobacterium tuberculosis Infection

Tuberculosis is the infectious disease with the worldwide largest disease burden and there remains a great need for better diagnostic biomarkers to detect latent and active M. tuberculosis infection. RNA molecules hold great promise in this regard, as their levels of expression may differ considerably between infected and uninfected subjects. We have measured expression changes in the four major classes of small noncoding RNAs in blood samples from patients with different stages of TB infection. We found that, in addition to miRNAs (which are known to be highly regulated in blood cells from TB patients), expression of piRNA and snoRNA is greatly altered in both latent and active TB, yielding promising biomarkers. Even though the functions of many sncRNA other than miRNA are still poorly understood, our results strongly suggest that at least piRNA and snoRNA populations may represent hitherto underappreciated players in the different stages of TB infection.

In tuberculosis (TB), as in other infectious diseases, studies of small noncoding RNAs (sncRNA) in peripheral blood have focused on microRNAs (miRNAs) but have neglected the other major sncRNA classes in spite of their potential functions in host gene regulation. Using RNA sequencing of whole blood, we have therefore determined expression of miRNA, PIWI-interacting RNA (piRNA), small nucleolar RNA (snoRNA), and small nuclear RNA (snRNA) in patients with TB (n = 8), latent TB infection (LTBI; n = 21), and treated LTBI (LTBItt; n = 6) and in uninfected exposed controls (ExC; n = 14). As expected, sncRNA reprogramming was greater in TB than in LTBI, with the greatest changes seen in miRNA populations. However, substantial dynamics were also evident in piRNA and snoRNA populations. One miRNA and 2 piRNAs were identified as moderately accurate (area under the curve [AUC] = 0.70 to 0.74) biomarkers for LTBI, as were 1 miRNA, 1 piRNA, and 2 snoRNAs (AUC = 0.79 to 0.91) for accomplished LTBI treatment. Logistic regression identified the combination of 4 sncRNA (let-7a-5p, miR-589-5p, miR-196b-5p, and SNORD104) as a highly sensitive (100%) classifier to discriminate TB from all non-TB groups. Notably, it reclassified 8 presumed LTBI cases as TB cases, 5 of which turned out to have features of Mycobacterium tuberculosis infection on chest radiographs. SNORD104 expression decreased during M. tuberculosis infection of primary human peripheral blood mononuclear cells (PBMC) and M2-like (P = 0.03) but not M1-like (P = 0.31) macrophages, suggesting that its downregulation in peripheral blood in TB is biologically relevant. Taken together, the results demonstrate that snoRNA and piRNA should be considered in addition to miRNA as biomarkers and pathogenesis factors in the various stages of TB.

Neurosurgical treatment of leprosy neuropathy in a low-incidence, European country

INTRODUCTION

Leprosy is nowaday increasingly encountered in non-endemic countries. Nerve involvement is common. Swelling of the nerves may lead to entrapment neuropathy causing pain and neurological deficits. Delay in diagnosis and treatment may lead to loss of chance of improvement. Surgical decompression in conjunction with medical therapy allows relief of symptoms.

METHODS

We present a retrospective series of 21 patients surgically treated in our center for leprosy entrapment neuropathy. We report presentation, treatment, and outcome at follow-up including a brief literature review.

RESULTS

Twenty-one patients were treated for nerve entrapments in four different anatomical districts. We reported good clinical outcomes mainly in motor deficits but also in improvement of sensitive deficits and pain symptoms. We did not experience surgical complications.

DISCUSSION

Although there is a lack of high-quality prospective studies comparing medical and surgical treatment of leprosy neuropathy, benefits of surgery are widely reported in series and case reports from endemic countries. There is scant literature from low-incidence countries even if leprosy incidence is nowaday increasing in these countries and will likelihood further increase in the future. Our results are in line with the literature presenting good outcomes after surgery.

CONCLUSION

We believe that a precise knowledge of the pathology and its management is crucial also for physicians who work in low-incidence countries to maximize healing chances with timely diagnosis and treatment.

Nanopharmaceuticals as a solution to neglected diseases: Is it possible?

The study of neglected diseases has not received much attention, especially from public and private institutions over the last years, in terms of strong support for developing treatment for these diseases. Support in the form of substantial amounts of private and public investment is greatly needed in this area. Due to the lack of novel drugs for these diseases, nanobiotechnology has appeared as an important new breakthrough for the treatment of neglected diseases. Recently, very few reviews focusing on filiarasis, leishmaniasis, leprosy, malaria, onchocerciasis, schistosomiasis, trypanosomiasis, and tuberculosis, and dengue virus have been published. New developments in nanocarriers have made promising advances in the treatment of several kinds of diseases with less toxicity, high efficacy and improved bioavailability of drugs with extended release and fewer applications. This review deals with the current status of nanobiotechnology in the treatment of neglected diseases and highlights how it provides key tools for exploring new perspectives in the treatment of a wide range of diseases.

Correlation between nerve growth factor and tissue expression of IL-17 in leprosy

Leprosy is a serious public health problem in peripheral and developing countries. Leprosy is a chronic infectious-contagious disease caused by the intracellular, bacillus Mycobacterium leprae, which causes tissue damage and demyelination of peripheral nerves. Recent studies have demonstrated the participation of new subtype's cytokines profile in the inflammatory response of leprosy. Since nerve functions are affected by inflammatory response during the course of leprosy, changes in the production of NGF and its receptor (NGF R) may be directly associated with disability and sensory loss. Skin biopsies were collected and submitted to immunohistochemistry using specific antibodies to IL-17, NGF and NGF R. Quantitative analysis of NGF, NGFR and IL-17 immunostaining showed a significant difference between the clinical forms, with higher expression of NGF and NGFR in lepromatous leprosy and IL-17 in tuberculoid leprosy. The present study showed that IL-17, in addition to stimulating an inflammatory response, negatively regulates the action of NGF and NGF R in the polar forms of the disease.

Laryngeal involvement causing dysphonia in a 29 year old nursing mother with lepromatous leprosy

Leprosy is a granulomatous disease that mainly affects the skin and peripheral nerves. It is caused by infection with mycobacterium leprae or mycobacterium lepromatosus. In most instances, diagnosis of leprosy can easily be made based on the clinical signs and symptoms. However, when patients present with atypical features, clinical diagnosis can be a challenge. We report a case of a nursing mother with lepromatous leprosy who presented with dysphonia and skin lesions initially thought to be a deep cutaneous mycosis.