A Case Series of Histoid Leprosy with a Brief Comparison of the Clinical Features with that of Lepromatous Leprosy

Histoid leprosy (HL) is a rare highly bacilliferous variant of lepromatous leprosy (LL). We are describing here a case series of HL in a tertiary care centre along with a comparison of the clinical features with cases of LL encountered in the same centre. There were 6 cases of HL in our centre for the past 10 years accounting for 1.86% of the total number of leprosy cases. HL constituted 11.54% of the total LL cases. 4 cases were de novo HL and 2 cases due to relapse. Papules, plaques and nodules were the commonest primary skin lesions. The distribution was localised in HL, mainly confined to the upper and lower limbs, while in LL it was symmetrical and generalised and mainly localised to the trunk. Superciliary madarosis, ear lobe infiltration, glove and stocking type of anaesthesia were found in the majority of LL, while lacking in HL patients. Type 2 lepra reaction and Grade 2 disability was much more common in LL, than HL. A very important finding in this case series is that the mean BI and MI of HL was more than in LL. All the patients were given of MB-MDT for 12 months and in patients who had initial BI of 4+ or more were given 24 months treatment and there were no cases of relapse after release from treatment

Lepromatous Spectrum -Unnoticed Or Overlooked Retrospective Analysis Of Lepromatous Spectrum Of Hansen's Disease In A Tertiary Care Centre

Introduction: Leprosy is a chronic granulomatous disease presents variedly depending on the patient's immune status at the time of infection. In this study, we are planning to perform a retrospective analysis to characterise the trend of Lepromatous spectrum of Hansen's disease cases registered in Tertiary care centre. To analyse the incidence,Aim: clinical patterns and variants of Lepromatous spectrum of Hansen's disease cases registered in Tertiary care centre. Objectives: To describe the epidemiological trend of Lepromatous Spectrum of Hansen's Disease and its clinical variants. A Retrospective observational study involving Lepromatous spectrum of Hansen's diseaseMethodology cases registered in leprosy clinic in last 5 years (2017-2021). Patient demographic details, duration of disease, clinical presentations , investigation details like slit skin smear, biopsy reports, treatment data was extracted from the Leprosy case register and data analysis was done in this study. 129 leprosy patients (BL-69, LL-43, Histoid-15, PureResults neuritic-2) reported during the period of 2017 to 2021[ 5 years]. 2018and 2019 had maximum number of cases approximately 30 new cases of leoromatous leprosy . Hypopigmented patches and glove & stocking anaesthesia seen in 59.8% cases, skin nodules seen in 45.7%, earlobe infiltration seen in 21.7%, epistaxis &saddle nose deformity seen in 4.3%, gynaecomastia seen in 2.2%, trophic ulcer seen in 26.1% at the time of presentation mainly involving the foot followed by hands, only nerve involvement without skin lesion present in 1.1% of cases. Claw hand was the most common deformity witnessed . The presence of Wartenberg sign was observed in 10 patients. Apart from ulnar and common peroneal nerve involvement present in 100 %of the patients, other peripheral nerves were involved in significant number of patients.All these patients showed positive acid fast bacilli in slit skin smear . Active surveillanceConclusion and early detection of the disease are imperative to prevent the spread of M. leprae. It is essential for timely implementation of treatment which will prevent deformities and disabilities. Active case detection plays the major role in early diagnosis of leprosy.

A Case of Lepromatous Leprosy with Laryngeal Involvement Presenting as Dysphonia

Involvement of larynx is a uncommon manifestation but could be the first time when the patient may be reporting to a specialist. This is the case report of a 65-year-old man who presented with dysphonia, was evaluated and was diagnosed as lepromatous leprosy with laryngeal involvement. On clinical examination the patient was found to have signs of leprosy – leonine face, nodular involvement of ears, madarosis, oedema of hands and feet, trophic ulcer on right foot. Bilateral greater auricular nerves were found to be enlarged. Video laryngoscopy revealed pale edematous epiglottis, arytenoid and aryepiglottic folds, with nodules on epiglottis. Biopsy from aryepiglottic fold and skin both was done. The diagnosis of lepromatous leprosy was confirmed with histopathology of biopsy from both skin and epiglottic fold. MRI imaging of the neck with contrast showed diffuse hyperintensity in the glottic-supraglottic larynx with asymmetry in the aryepiglottic fold and vocal cord. This experience shows that clinical suspicion is most critical element in reaching the diagnosis of leprosy

Bilateral Groove Sign in Lepromatous Leprosy with Type 2 Lepra Reaction – An Uncommon Presentation

A 35-year-old male patient presented with tingling and numbness over both extremities, skin lesions and buboes in bilateral inguinal region with the classical “sign of groove”. Biopsy from the skin lesion as well as the lymph node aspirate was consistent with lepromatous leprosy with erythema nodosum leprosum (type 2 lepra reaction). This case report highlights the interesting observation of the “groove sign” with leprosy, as a result of lymph node involvement of inguino-femoral region

Corneal Leproma : A Rare Ocular Manifestation in Leprosy

A leproma is a discrete granulomatous nodule rich in lepra bacilli and is a rare yet characteristic finding seen in the lepromatous spectrum of Hansen’s disease. Majority of the ocular lepromas reported in the literature so far arise from uveal tissue and sclera with an incidence of 0.75 to 1%. Exclusive corneal leproma associated with multibacillary leprosy is an extremely rare finding. It is painless and silent nature in earlier stages because of that it may remain unattended for several years until significant visual loss, disease progression and transmission may continue to occur. We report a case having corneal leproma, the detection of which led to the uncovering of advanced cutaneous involvement. The patient had chosen not to disclose his skin involvement and disability possibly due to social stigma and partly due to ignorance. The presence of such untreated multi-bacillary forms in the community may present a significant hurdle for a country like ours, aiming to eliminate this chronic disease. Public awareness through health education coupled with early detection remains the cornerstone in tackling this multi-system disorder which has implications both from disability and transmission angles

Fenómeno de Lucio como forma de presentación de enfermedad de Hansen / Lucio's phenomenon as a presentation of Hansen disease / Fenômeno de Lucio como forma de apresentação da hanseníase

Resumen: Introducción: la enfermedad de Hansen es una enfermedad infecciosa crónica, causada por Mycobacterium leprae, que afecta principalmente piel y nervios periféricos. Las reacciones leprosas son eventos agudos que se asocian a un aumento de la morbimortalidad de la enfermedad. Objetivo: presentar el caso clínico de un paciente con fenómeno de Lucio, a través del cual se llegó al diagnóstico de enfermedad de Hansen, y remarcar la importancia de tener presente esta enfermedad, poco frecuente en nuestro país, para su correcto diagnóstico. Discusión: el fenómeno de Lucio es un tipo de reacción leprosa mediada por inmunocomplejos. Se caracteriza clínicamente por máculas o placas eritematovioláceas, de aparición súbita, que evolucionan a úlceras necróticas y curan dejando cicatrices estrelladas atróficas. De no mediar tratamiento, puede ser fatal, debido a sobreinfección y sepsis. Este se basa en el tratamiento específico de la infección, asociado a prednisona y un correcto manejo de las heridas.

Summary: Introduction: Hansen disease is a chronic infectious disease caused by Mycobacterium leprae, which mainly affects the skin and peripheral nerves. Leprosy reactions are acute events associated to an increase in the morbimortality of the disease. Objective: the study aims to present the clinical case of patient with Lucio´s phenomenon, which allowed the diagnosis of Hansen disease, and to emphasize on the importance of having this disease in mind for an appropriate diagnosis, despite it being rather unusual in our country. Discussion: Lucio´s phenomenon is a kind of leprosy reaction mediated by immune complexes. Clinically, it is characterized by the sudden onset of macules or blue hemorrhagic plaques, with a rapid evolution to necrotic ulcers, and it heals leaving star-shaped atrophic scars. If it is not treated, it may be fatal due to superinfection and sepsis. Treatment is based on specific medication for the infection, associated to prednisone and the correct handling of injuries.

Resumo: Introdução: a hanseníase é uma doença infecciosa crônica causada pelo Mycobacterium leprae, que acomete principalmente pele e nervos periféricos. As reações hansênicas são eventos agudos que estão associados ao aumento da morbimortalidade da doença. Objetivo: apresentar o caso de um paciente com fenômeno de Lúcio, por meio do qual se chegou ao diagnóstico de hanseníase, e ressaltar a importância de se ter em mente esta doença, rara em nosso meio, para seu correto diagnóstico. Discussão: o fenômeno de Lúcio é um tipo de reação hansênica mediada por imunocomplexos. Caracteriza-se clinicamente por máculas ou placas eritêmato-violáceas de início súbito que evoluem para úlceras necróticas e cicatrizam, deixando cicatrizes estreladas atróficas. Sem tratamento pode ser fatal, devido a superinfecção e sepse; a terapia está baseada no tratamento específico da infecção, associado à prednisona e no manejo correto da ferida.

Fenómeno de Lucio. A propósito de un caso / Lucio´s phenomenon. About a case

El fenómeno de Lucio es un estado reaccional grave, poco frecuente, mediado por inmunocomplejos que se observa típicamente en los casos de lepra lepromatosa difusa. En Paraguay, corresponde aproximadamente al 2% de los casos de lepra diagnosticados en la mayoría de los casos, se presenta como debut de la enfermedad. Se manifiesta con lesiones en la piel de tipo máculas y placas purpúricas poligonales, generalmente sin compromiso visceral. El diagnóstico lo confirma el estudio histopatológico y es fundamental realizar el diagnóstico diferencial con vasculitis de otras etiologías.

Lucio's phenomenon is a rare and severe reactional state mediated by immune complexes that is commonly seen in cases of diffuse lepromatous leprosy. In Paraguay, it represents approximately 2% of leprosy diagnosed cases, mainly as a debut of the disease. It manifests with macule-type skin lesions and polygonal purpuric plaques, generally without visceral involvement. The diagnosis is confirmed by the histopathological study and it is essential to consider differential diagnosis such as vasculitis of other etiologies.

Progressive neuropathy in patients with lepromatous leprosy after multidrug therapy

BACKGROUND The lepromatous pole is a stigmatising prototype for patients with leprosy. Generally, these patients have little or no symptoms of peripheral nerve involvement at the time of their diagnosis. However, signs of advanced peripheral neuropathy would be visible during the initial neurological evaluation and could worsen during and after multidrug therapy (MDT). Disabilities caused by peripheral nerve injuries greatly affect these patients' lives, and the pathophysiological mechanisms underlying nerve damage remain unclear. OBJECTIVES To evaluate the outcome of peripheral neuropathy in patients with lepromatous leprosy (LL) and persistent neuropathic symptoms years after completing MDT. METHODS We evaluated the medical records of 14 patients with LL who underwent nerve biopsies due to worsening neuropathy at least four years after MDT. FINDINGS Neuropathic pain developed in 64.3% of the patients, and a neurological examination showed that most patients had alterations in the medium- and large-caliber fibers at the beginning of treatment. Neurological symptoms and signs deteriorated despite complete MDT and prednisone or thalidomide use for years. Nerve conduction studies showed that sensory nerves were the most affected. MAIN CONCLUSIONS Patients with LL can develop progressive peripheral neuropathy, which continues to develop even when they are on long-term anti-inflammatory and immunosuppressive therapy.

Lepra lepromatosa nodular de diagnóstico tardío procedente de la Amazonía peruana, con el desarrollo de una reacción tipo 2 / Late diagnosis nodular lepromatous leprosy from the Peruvian Amazon, with development of a type 2 reaction

Resumen La lepra o enfermedad de Hansen es una de las clásicas enfermedades olvidadas que aún persiste en Perú. La infección es ocasionada por Mycobacterium leprae. La enfermedad varía en un amplio rango de manifestaciones desde la lepra tuberculoide (paucibacilar) hasta la lepromatosa (multibacilar). Se presenta el caso de un varón de 55 años, agricultor y extractor de madera, procedente de la Amazonia peruana, con lesiones cutáneas antiguas infiltrantes en la cara, cuello, tórax, abdomen y extremidades. La baciloscopia y estudio histológico de una biopsia de piel confirmaron la presencia de bacilos ácido-alcohol resistentes. Se concluyó, en forma tardía, que fue un caso de lepra lepromatosa nodular. Recibió terapia con rifampicina, dapsona y clofamizina por dos años con una lenta mejoría; no obstante, cursó con un eritema nodoso leproso (reacción tipo 2) con buena respuesta a corticoesteroides y talidomida.

Abstract Leprosy or Hansen's disease is one of the classic neglected diseases that still persists in Peru. The infection is caused by Mycobacterium leprae. The disease varies in a wide range of manifestations from tuberculoid (paucibacillary) to lepromatous (multibacillary) leprosy. We present the case of a 55-year-old man, farmer and wood extractor, from the Peruvian Amazon with old infiltrating cutaneous lesions on the face, neck, thorax, abdomen and extremities. The smear and biopsy examinations confirm the presence of acid-alcohol-resistant bacilli compatible with leprosy. It is concluded, with a long delay, it was a case of nodular lepromatous leprosy. He received therapy with rifampicin, dapsone and clofamizine for two years with slow progressive improvement; however, he presented an erythema nodosum leprosum (type 2 reaction) with response to corticosteroids and thalidomide.

A Case of Lepromatous Leprosy in Oregon

The cases of leprosy occur rarely in North America and a health care professional may not readily consider a diagnosis of leprosy. We encountered a 23-year-old female with hypopigmented macules and painful nodules along with peripheral neuropathy in Oregon, who had immigrated from Micronesia. A skin biopsy confirmed the diagnosis of leprosy. Patient developed a type 2 reaction, Erythema nodosum leprosum, upon initiation of the multidrug therapy. It is vital to recognize the signs and symptoms of leprosy and associated reactions so the patient can be treated appropriately to prevent debilitating and stigmatizing neurocutaneous and systemic illness.

Pseudodactylitis : A unique Manifestation of Lepromatous Leprosy

Leprosy has many unique manifestations, sometimes delaying the actual diagnosis. Arthitis in leprosy is a common rheumatologic manifestation seen in lepra reactions. Diffuse fusiform digital swelling termed as dactylitis may occur secondary to leprosy arthritis and enthesitis. These presentations are common in other rheumatologic disorders and may cause diagnostic dialemma till neurologic manifestations of leprosy are evident. We present a case of lepromatous leprosy in an Indian patient manifesting as pseudodactylitis and nodular lesions over forehead. On examination he had enlarged peripheral nerves and sensory loss over distal limbs. Slit skin smear was positive for lepra bacilli and patient was treated with WHO - MDT multibacillary regimen. This report highlights the unique manifestation of lepromatous leprosy which requires a high index of suspicion for diagnosis.

Lepra lepromatosa macular en la infancia. Presentación de un caso / Lepromatous macular leprosy in childhood. Presentation of a case / Lepra macular lepromatosa na infância. Apresentação de um caso

RESUMEN Introducción: la lepra es una enfermedad infectocontagiosa causada por el mycobacterium leprae, llamada también enfermedad de Hansen en honor a quien descubrió la bacteria en 1873, presenta varias formas clínicas y estados reaccionales que dependen de la inmunidad especifica del huésped. Presentación de caso: paciente masculino de 12 años con diagnóstico de lepra lepromatosa macular caracterizada por máculas hipocrómicas anestésicas y neuritis periférica bilateral y simétrica de los nervios: auricular mayor y cubital, la baciloscopia negativa y el resultado de la histología probablemente lepra. Discusión: en el campo de la Dermatopediatría la lepra sigue siendo una patología poco descrita y subvalorada en la consulta diaria, por ello se convierte en un desafío diagnóstico, debido a la diversidad de manifestaciones clínicas que se pueden presentar, es necesario un minucioso examen cutáneo-neural en todo niño, que presente lesiones cutáneas sugestivas y fuente infecciosa sospechosa. Conclusiones: la presencia de máculas hipocrómicas anestésicas y neuritis periférica bilateral y simétrica de los nervios: auricular mayor y cubital, la presencia antecedentes familiares con la enfermedad y histología probablemente lepra contribuyeron al diagnóstico de una lepra lepromatosa macular.

ABSTRACT Introduction: leprosy is an infectious disease caused by mycobacterium leprae, also called Hansen's disease in honor of the one who discovered the bacteria in 1873. It has several clinical forms and reaction states that depend on the specific immunity of the host. Case presentation: a 12-year-old male patient with a diagnosis of lepromatous macular leprosy, characterized by hypochromic anesthetic macules and bilateral symmetric peripheral neuritis of the nerves: major and ulnar auricular, negative smear and the result of probably leprosy histology. Discussion: in the field of Dermatopediatrics, leprosy is still a pathology that is little described and undervalued in the daily practice, therefore it becomes a diagnostic challenge, due to the diversity of clinical manifestations that may occur, a thorough skin examination is necessary -neural in every child, presenting suggestive skin lesions and suspicious infectious source. Conclusions: the presence of hypochromic anesthetic maculae and bilateral symmetric peripheral neuritis of the nerves: major and ulnar auricular, presence of family history with the disease and probably leprosy histology contributed to the diagnosis of lepromatous macular leprosy.

RESUMO Introdução: A hanseníase é uma doença infecciosa causada pelo Mycobacterium leprae, também chamada de doença de Hansen em honra de quem descobriu a bactéria em 1873, tem várias formas clínicas e estados reacionais que dependem de imunidade do hospedeiro específico. Relato de caso: Paciente do sexo masculino de 12 anos com diagnóstico de lepromatous macular caracterizada por máculas hipocrômicas e neurite periférica bilateral simétrica anestésico eo nervo: auricular e ulnar, o resultado esfregaço negativo e histologia provavelmente lepra. Discussão: No campo da Dermatopediatría lepra é ainda um pouco descrita e subestimado na prática patologia diária, portanto, torna-se um desafio diagnóstico por causa da diversidade de manifestações clínicas que podem ocorrer, um exame da pele completa é necessária -neural em todas as crianças, apresentando lesões cutâneas sugestivas e fonte infecciosa suspeita. Conclusões: A presença de máculas hipocrômicas e nervos neurites periféricas bilaterais e simétricas anestésicos: auricular ulnar e a história da família presença da doença e da lepra histologia provavelmente contribuiu para o diagnóstico de lepromatous macular.

Aspectos clínicos y epidemiológicos en pacientes timorenses con enfermedad de Hansen / Clinical and epidemiological aspects in Timor patients with the Hansen disease

Se realizó un estudio observacional, descriptivo y transversal de 14 pacientes con lepra, diagnosticados y atendidos en la consulta de Dermatología del Hospital Nacional Guido Valadares, en Dili, Timor Oriental, de julio a diciembre del 2015, con vistas a caracterizarles y describir algunos aspectos clínicos y epidemiológicos de la enfermedad. En la serie se obtuvo una mayor frecuencia de pacientes en el grupo etario de 26 a 35 años y del sexo masculino, la forma clínica predominante fue la multibacilar y el tiempo de evolución de los síntomas hasta que fuera establecido el diagnóstico fue de menos de un año. Igualmente, en la mayoría existieron reacciones agudas, principalmente de tipo II o eritema nudoso leproso, y diferentes grados de discapacidad.

An observational, descriptive and cross-sectional study of 14 patients with leprosy, diagnosed and assisted in the Dermatology Service of Guido Valadares National Hospital, in Dili, Timor Lester was carried out from July to December, 2015, with the aim of characterizing them and to describe some clinical and epidemiological aspects of the disease. In the series a higher frequency of patient was obtained in the age group 26 to 35 years and of the male sex, the predominant clinical form was the multibacilar and the time of clinical course of the symptoms up to reaching the diagnosis was shorter than a year. Equally, in most of them acute reactions were presented, mainly of type II or from the erythema leprosy group, and different degrees of inability.

An Unusual Case of Lepromatous Leprosy with Elastolysis and Atrophic Lesions

A 48-year-old lady presented with multiple, asymptomatic papules on upper trunk and upper extremities of 4 years duration. She gave a history of similar lesions/papules which used to heal earlier also, in a couple of weeks/months with atrophy. She had consulted many physicians and dermatologists without any relief. Biopsy from a papule showed dense nodular collection of foamy histiocytes in dermis in close proximity of neurovascular bundle. Special stain revealed absent elastic fibres in areas with infiltration. The case was diagnosed as lepromatous leprosy with elastolysis. Unusual features observed in the patient were predominant involvement of sun-exposed areas and atrophy. These signs and symptoms in the patient probably, mislead clinicians away from the diagnosis of leprosy.

Gyrate Erythema like Manifestation - An Unusual Presentation of Borderline Lepromatous Hansen's Disease

Leprosy is a chronic granulomatous disease caused by Mycobacterium leprae. Once considered a taboo, it is still misdiagnosed and underdiagnosed. Leprosy can present in innumerable diverse ways which can be confused with many treatable and non-treatable, infectious and noninfectious disorders. Though leprosy is eliminated from India in 2005, still many new cases are being reported day by day. Here we found a very rare manifestation of borderline lepromatous leprosy presented with erythematous figurate bands over trunk, proximal extremities and erythematous patches over palms and soles.

Bullous Erythema Nodosum Leprosum: A Rare Entity

Erythema Nodosum Leprosum (ENL) usually presents in patients with Lepromatous Leprosy. It commonly presents as tender erythematous nodules but other rare forms like pustular, vesicular, bullous or necrotic have also been reported. We report a case of a 30 year old male who initially presented with erythematous tender nodules and plaques over both lower limbs with a past history of being treated for Lepromatous Leprosy. He further developed bullous lesions over the same sites. Biopsy specimen of a bulla was sent for histopathology which was suggestive of ENL. This presentation of ENL makes it an interesting case to be reported.

Lepra lepromatosa no erradicada en el perú / Leprosy lepromatosa not eradicated in peru

RESUMEN En este estudio del caso, los autores discuten la presentación de un varón de 56 años, con lepra lepromatosa multibacilar, localizado en un hospital del distrito de Trujillo. La biopsia de una de las lesiones, demostró infiltraciones difusas por macrófagos espumosos en toda su extensión; con la tinción de Ziehl - Neelsen se encuentran: bacilos ácido-alcohol resistentes sueltos o empaquetados en grupos, con índice bacilar: 6. La condición se manejó inicialmente en la comunidad como un "pénfigo ampolloso", sugiriendo que las barreras locales actualmente impiden la detección de la lepra en este sistema de atención primaria, en desarrollo. La lepra es una enfermedad multisistémica y el paciente demostró alteraciones neurológicas periféricas evidentes. Promover el conocimiento de estas manifestaciones sistémicas, evitará un retraso en el diagnóstico, a su vez disminuirá las complicaciones y eludirá la morbilidad a largo plazo. Los esfuerzos para optimizar los sistemas de detección, gestión, educación pública y profesional son esenciales, para impulsar la erradicación en estas poblaciones en riesgo.

SUMMARY In this case study, the authors discuss the presentation of a 56-year-old male in a hospital in the Trujillo district with lepromatous multibacillary leprosy. The biopsy of one of the lesions showed diffuse infiltrations by foamy macrophages in all its extension, with the stain of Ziehl - Neelsen bacilli acid resistant alcohol loose or packaged in groups, the bacilar index: 6. The condition was initially managed in the community as a "bullous pemphigus" that suggests that local barriers currently prevent the detection of leprosy in this developing primary care system. Leprosy is a multisystem disease and the patient demonstrated evident peripheral neurological alterations. Promoting the knowledge of these systemic manifestations will avoid a delay in the diagnosis, in turn will reduce complications and avoid long-term morbidity. Efforts to optimize detection systems, management and public and professional education are essential to promote eradication in these populations at risk.

A curious case of Lepromatous Leprosy Developing Complete loss of Pigmentation, followed by Reappearance of Pigmentation with Multi Drug Therapy (MDT) alone - A Support for Neural Theory of Vitiligo Pathogenesis?

Lepromatous leprosy is a multisystem disease characterized by a decline in delayed hypersensitivity to Mycobacterium leprae antigens, causing multiplication of bacilli in huge numbers. We herein report a case of an adult male with lepromatous leprosy who was started on adult multibacillary multi-drug therapy. With treatment, the surface of lesions developed depigmented macules and patches. However, on continuation of antileprotic drugs, there was progressive perifollicular as well as inter-follicular re-pigmentation. This case clinically depicts re-pigmentation of depigmented skin following multidrug therapy for leprosy supporting the role of neural system in the homeostasis of melanocytes.

A Rare Presentation of Histoid Leprosy: A Case Report

Histoid Leprosy is an expression of multibacillary leprosy, characterized by typical cutaneous and subcutaneous nodules and plaques present over an apparently normal skin and histopathologically the predominance of spindle-shaped cells or polygonal cells and unusually large number of acid fast bacilli. We report a case of histoid leprosy which was insidious in onset with multiple discrete lesions after release from treatment as a case of Hansen's disease seven years back. Initial FNAC report from a lesion revealed hemangioma which was unusual in presentation. He was later diagnosed clinically and histopathologically as a case of histoid leprosy.