Granulomatous Dermatitis Research Articles

Clinico-histopathological characteristics and management outcome of rare chronic infective granulomatous diseases: A case series study

Granulomatous skin diseases are common cutaneous dermatoses commonly encountered by practicing dermatologist. Granulomatous skin lesions are distinctive pattern of chronic inflammatory response of skin due to reaction against various organic and inorganic antigens. Granulomas are characterized by focal collection of epithelioid cells or histiocytes, admixed with variable number of leucocytes (especially mononuclear cells) and multinucleated giant cells. Granulomatous reaction is a type IV hypersensitivity reaction evoked by poorly soluble reactive substances. Incidence and prevalence of different types of granulomatous dermatitis depend on geographic location. Granulomatous skin lesions are common in the eastern parts of India. Many granulomatous skin lesions have identical histomorphology and conversely a single pathology can produce varied histological features. Some rare suppurative chronic granulomatous skin diseases include Botryomycosis, Actinomycosis, Rhinosporoidosis, Nocardiosis, and Cutaneous Tuberculosis. To describe clinical, histopathological features and treatment outcome of rare chronic infective granulomatous diseases. In this observational case series study, we retrospectively analysed six biopsy proven cases of rare chronic infective granulomatous diseases presented to our department (OPD) of Dermatology, Venereology and Leprosy (DVL) over a period of six months between June 2023 to November 2023 at Great Eastern Medical School and Hospital (GEMS), Srikakulam, Andhra Pradesh, India. The patient’s full clinical history, morphology of lesions, histopathological findings and treatment outcome were analysed. Along with histopathology, other necessary laboratory investigations were performed if required. A total of six patients were involved in the study, of whom four were males and two were females. The male to female ratio was 2:1, with a slight male majority. The most common age group was 31-40 years for both males and females. Painful raised lesion for long duration was the predominant complaint among those patients. Out of these six rare chronic granulomatous diseases, bacterial infections were common than fungal infection. All the cases showed clinical improvement after one month of starting treatment.: Most of the patients had a chronic history with improper treatment. So, it is imperative that the clinical diagnosis has to be confirmed with histopathology for the definitive diagnosis and appropriate treatment of these rare chronic infective granulomatous diseases. All these rare cases showed excellent progress after starting the right treatment.

P55 The boggy uveitis

Abstract Introduction Blau syndrome is a rare autosomal dominant autoinflammatory disease that affects young children. Typically, it causes widespread granulomatous inflammation, causing uveitis, arthritis, and dermatitis. The triad may be characteristic of the disease but is not present in all cases and may occasionally be incomplete. A characteristic finding is the presence of boggy swellings in the involved joints. Our patient presented with uveitis and boggy swellings of the wrists without arthritis. The history of dermatitis was remote. A high clinical index of suspicion and exome sequencing are imperative to make this rare diagnosis. Case description A six-year-old female was brought to an ophthalmologist with a complaint of a progressive decrease in vision in both eyes over the last four months. The vision deteriorated rapidly over the last couple of months. A detailed eye examination revealed features of granulomatous posterior uveitis with bilateral inflammatory cataracts. She was referred to the Rheumatology Outpatient Clinic. A detailed examination revealed boggy swellings on the bilateral wrist joints. As per the father, these swellings had been present for the last four years. The child never complained of pain in the wrists, or swelling and/or pain in any other joint. There was no history suggestive of arthritis or uveitis in the parents or immediate family members. The child occasionally developed an itchy red rash on the back. Such a rash has not occurred for the last many months. There was no skin lesion at the time of the examination. Suspecting Blau syndrome, a blood sample was sent for clinical exome sequencing (CES). Surgery (cataract extraction and intraocular lens implantation) was performed in the right eye. Intraoperative findings were noted, and features of granulomatous uveitis were evident. The patient was initiated on oral corticosteroids at 1 mg/kg of prednisolone by the eye surgeon. Four weeks later, the CES result was reported; it was positive for a heterozygous ‘pathogenic’ variant (detected in exon 4 of the NOD2 gene). The patient was reviewed after the report, and methotrexate was added. We started tapering the corticosteroids after six weeks of initial therapy. On the last eye examination (three months after the surgery), the uveitis had subsided. The vision was normal in the operated eye and had considerably improved in the unoperated eye. The surgery for the left eye was now deemed non-obligatory and was thus deferred. Discussion Blau syndrome is a rare autosomal dominant syndrome that causes arthritis, dermatitis, and granulomatous uveitis in children. A characteristic clinical feature of Blau syndrome is the presence of boggy swellings in the involved joints. Skin involvement usually occurs before the onset of arthritis and uveitis, presenting in the form of a rash (macro or micropapular and scaly), and occurs in infancy. Arthritis appears subsequently (between two and four years of age), followed by uveitis (around four years of age). Other uncommon manifestations of this disease are lymphadenopathy, sialadenopathy, erythema nodosum, neuropathies, leukocytoclastic vasculitis, glomerular and interstitial nephritis, interstitial lung disease, and pericarditis. A close mimic of this disease is sarcoidosis. Blau syndrome is an autosomal dominant disorder due to a mutation in the caspase recruitment domain gene CARD15/NOD2. There is no consensus on the optimal treatment for Blau syndrome. Corticosteroids and immunosuppressive agents, including methotrexate and azathioprine, have been used. Biologic agents have also been used with good results. In our case, the patient never had joint pains. He did not seek help until the child’s vision was impaired. Commonly, the ophthalmologist may be the only qualified physician of first contact. Joint pains may often be treated with self-medication or may be labelled as “growing pains” but the loss of vision is an unignorable catastrophic symptom and is invariably reported. The alert eye specialist must also enquire about fever, arthritis, and dermatitis in children with granulomatous uveitis. This correlation must be made sooner rather than later to prevent delay in diagnosis and therapy. The temporal dispersion of symptoms, i.e., the occurrence of different symptoms at different ages in the affected individual, also makes the diagnosis of Blau syndrome very challenging. Key learning points • Blau syndrome is a rare autosomal dominant disorder due to a mutation in the caspase recruitment domain gene CARD15/NOD2. • It causes arthritis, dermatitis, and granulomatous uveitis. • A characteristic clinical feature of Blau syndrome is the presence of boggy swellings in the involved joints. • A strong index of suspicion is required for diagnosis of this rare disorder.

Pyoderma Gangrenosum-like Ulcers Associated Granulomatosis with Polyangiitis

Granulomatosis with polyangiitis is an ANCA-positive vasculitis primarily affectingsmall to medium-sized vessels, typically involving the lungs and kidneys. This articlepresents a remarkable case of a patient with an unusual pyoderma gangrenosum-likeulcer on the face and granulomatosis with polyangiitis. A 28-year-old man, previouslydiagnosed with granulomatosis with polyangiitis, presented at a dermatology clinic with a 6-month-old ulcer in the right preauricular region following a traumatic incident. A spindle biopsy revealed suppurative granulomatous dermatitis with secondary vascular damage, while cultures showed no signs of infection. The patient was subsequently treated with rituximab, leading to a positive clinical response. This case underscores the challenge of diagnosing this rare manifestation of granulomatosis with polyangiitis and suggests that rituximab could be a valuable treatment option.

Narrowband Ultraviolet B Phototherapy for Generalized Granuloma Annulare: Real-Life Experience and Review of the Literature.

Generalized granuloma annulare (GA) is an uncommon noninfectious granulomatous dermatitis. Phototherapy is often considered first-line therapy, with more evidence for psoralen ultraviolet A than narrowband ultraviolet B (NB-UVB). We aimed to evaluate the effectiveness and safety of NB-UVB in generalized GA and to review the literature. In this observational, retrospective study, 11 patients with generalized GA who received NB-UVB between 2013 and 2023 were evaluated. Data from the patients were obtained from the phototherapy unit and clinical follow-up forms. Eleven patients, 10 (90.9%) female and 1 (9.1%) male were included in the study. The mean age of the patients was 57.6 ± 7.9 years. The mean disease duration was 26.9 ± 27.9 weeks. Three (27.2%) of the patients had interstitial GA. All patients showed improvement: NB-UVB therapy resulted in complete response in 18.2% of the patients and partial response in 81.8%. The mean number of NB-UVB sessions was 36.4 ± 13.8. The mean cumulative dose was 37.1 ± 25.6 J/cm2. There was no significant difference in the mean number of sessions and cumulative dose according to clinical response (P > .05). NB-UVB was extremely well tolerated. After phototherapy, patients were followed for at least 6 months; no relapses were observed. NB-UVB is an effective and safe treatment option in generalized GA.

Beyond rheumatoid nodules in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease predominantly affecting synovial joints. Extra-articular manifestations, including skin involvement, can also occur. The most frequent cutaneous manifestation in RA patients is rheumatoid nodules, occurring in 20-30% of seropositive individuals. These nodules are typically firm, painless, and located on pressure points such as the hands and elbows. However, in a minority of cases, other skin conditions can complicate RA, notably palisaded neutrophilic granulomatous dermatitis (PNGD). PNGD presents as erythematous papules or plaques, often pruritic and distributed symmetrically over extensor surfaces, making it challenging to differentiate from rheumatoid nodules. Histopathological examination is crucial to establish the diagnosis. High clinical suspicion and appropriate referral to Dermatology are essential for accurate diagnosis and management. Treatment of PNGD is focused on underlying disease control. Other options include topical, intralesional or systemic corticosteroids, dapsone or hydroxychloroquine. Herein, we present the case of a 71-year-old woman with RA who developed PNGD, highlighting the importance of a multidisciplinary approach for achieving a favorable clinical outcome.

Case report: Reactive granulomatous dermatitis presenting with inguinal erythematous plaques in a patient administered with pravastatin

An identical group of disorders has been called “interstitial granulomatous dermatitis” and “palisaded neutrophilic and granulomatous dermatitis.” In addition, a drug-induced subset of this condition has been named “interstitial granulomatous drug reaction (IGDR).” More recently, “reactive granulomatous dermatitis (RGD)” has been proposed as an umbrella term encompassing these three disorders. A considerable number of RGD cases are associated with systemic conditions, including autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus, inflammatory bowel disease, and malignancies. IGDR has also been shown to be caused by certain medications. We present a case of a 74-year-old Japanese man showing an asymptomatic, well-demarcated erythema eruption on the bilateral inguinal region extending to the lower abdomen and proximal thigh area. He had hyperlipidemia and had been taking pravastatin for 4 years. A biopsy specimen taken from the erythematous lesion revealed infiltration of lymphocytes and histiocytes in the upper and lower dermis. Interstitial infiltrates of histiocytes and lymphocytes were found as they were dispersed between collagen bundles. Immunostaining showed CD68+ macrophages intermingled with CD4+ and CD8+ T cells. Based on the clinical and histologic findings, the eruption was diagnosed as RGD. Because of the possibility of IGDR, pravastatin was stopped. His eruption completely disappeared within 6 months after the discontinuation. The list of drugs that cause RGD includes angiotensin-converting enzyme inhibitors, antihistamines, β-blockers, antidepressants, anticonvulsants, tocilizumab and ustekinumab. In addition, various statins have been reported to induce drug eruptions. The eruption types are mainly eczematous or lichenoid reactions, with psoriasiform or ichthyosiform reactions occurring rarely. There was only one report documenting that RGD occurred in patients administered rosuvastatin, with annular, violaceous plaques distributed on the extremities, proximal trunk and intertriginous areas. Pravastatin induces lichenoid eruption, but RGD has not been documented. Our case suggests that RGD is underestimated as an adverse effect of statins possibly because of its unusual cutaneous manifestations.

Proteomic Profiling of Tears in Blau Syndrome Patients in Identification of Potential Disease Biomarkers.

Blau syndrome (BS) is a rare autoinflammatory granulomatosis characterized by granulomatous arthritis, uveitis, and dermatitis. Ocular complications are particularly severe in BS, significantly contributing to morbidity. This study aims to identify potential biomarkers for BS ocular degeneration through proteomic profiling of tear samples from affected patients. Seven subjects from the same family, including four carriers of the BS-associated NOD2 mutation (p.E383K), were recruited alongside healthy controls. Tear samples were collected using Schirmer strips and analyzed via mass spectrometry. A total of 387 proteins were identified, with significant differences in protein expression between BS patients, healthy familial subjects, and healthy controls. Key findings include the overexpression of alpha-2-macroglobulin (A2M) and immunoglobulin heavy constant gamma 4 (IGHG4) in BS patients. Bioinformatic analysis revealed that differentially expressed proteins are involved in acute-phase response, extracellular exosome formation, and protein binding. Notably, neutrophils' azurophilic granule components, as azurocidin (AZU1), myeloperoxidases (MPO), and defensins (DEFA3), were highly expressed in the most severely affected subject, suggesting a potential role of neutrophils in BS ocular severity. These proteins might be promising biomarkers for ocular involvement in BS, facilitating early detection and tailored treatment strategies.

Eosinophilic Cellulitis (Well’s Syndrome) and Eosinophilic Granulomatosis with Polyangiitis (Churgg-strauss Syndrome); Different Clinical Entities, or a Single Spectrum of Disease? A Case Study, Discussion and Literature Review

This case study represents an unusual presentation female in her seventies who presented with a chronic eosinophilic rash without systemic involvement on a background of psoriatic arthritis (pSA) and Sjogren’s Syndrome (sSS). Biopsy of the lesions identified flame figures. The differentials for such lesions are wide, however this case discusses three of the most likely differentials including Eiosinophilic Cellulitis (Well’s Syndrome), Eosionophilic Granlomatosis with Polyangiitis (Churgg Strauss Syndrome) and Granulomatous Dermatitis (GD). A common aberrant eiosinophilic response is dicussed and a review of the literature identifies the possibility that these diagnoses represent a single spectrum of disease, rather than separate clinical entities. Whilst the provoking incident was not able to be established in this case, the possibility of covid-19 vaccination contributing to the development of lesions is discussed. This case highlights the importance of conducting skin biopsies of unusual lesions that do not follow an expected clinical course and that skin biopsies might need to be performed opportunistically by emergency departments especially in rural areas where dermatology services are lacking. A lack of knowledge of various complex systemic diseases that present with unusual skin lesions often results in missed diagnosis and delayed patient care. Education of primary care physicians and healthcare professionals working in emergency departments is required to ensure timely biopsy and appropriate serology with screening for underlying systemic diseases including malignancy is required to prevent missed diagnosis and delayed care.

The Histopathology of Vacuoles, E1 Enzyme, X-Linked, Autoinflammatory, Somatic Syndrome: Report of 12 Skin Biopsies From 6 Patients.

We present the histopathology of 12 skin biopsies from 6 patients with vacuoles, enzyme E1, X-linked, autoinflammatory, somatic syndrome and review the literature. The age of these 6 men ranges from 62 to 83 years (median of 70 years). UBA1 mutation was documented in all 6 patients. Multiple organ systems were involved with constitutional symptoms noted in 4 of 6 patients (67%), cutaneous involvement in 6 of 6 patients (100%), hematologic abnormalities in 6 of 6 patients (100%), pulmonary involvement in 4 of 6 patients (67%), musculoskeletal abnormalities in 3 of 6 patients (50%), vascular thrombosis in 2 of 6 patients (33%), ocular involvement in 2 of 6 patients (33%), and gastrointestinal involvement in 5 of 6 patients (83%). Of the 6 presented patients, neutrophilic dermatosis was seen in 3 biopsies, histiocytoid neutrophilic dermatosis in 1 biopsy, neutrophilic dermatosis with vasculitis in 1 biopsy, neutrophilic and granulomatous dermatitis in 2 biopsies, septal panniculitis consistent with erythema nodosum in 2 biopsies, and nonspecific patterns in 3 biopsies. In summary, neutrophilic dermatosis, small-vessel vasculitis, and panniculitis are frequent histopathologic patterns noted in decreasing frequency in skin biopsies of the patients with vacuoles, enzyme E1, X-linked, autoinflammatory, somatic syndrome. However, the histopathologic findings can be diverse, nonspecific in some instances, and varied among different biopsies obtained from the same patient.

Palisaded Neutrophilic and Granulomatous Dermatitis-Like Reaction Associated with Wilms Tumor 1 Protein-Derived Peptide Vaccine: A Case and Review of the Literature

Palisaded neutrophilic and granulomatous dermatitis (PNGD) is an inflammatory cutaneous reaction that is associated with underlying autoimmune diseases. In rare cases, PNGD has been attributed to systemic medications. Here we report one case of a cutaneous injection-site reaction that occurred after intradermal administration of an experimental Wilms Tumor 1 (WT1) protein-derived peptide vaccine in a woman being treated for recurrent ovarian cancer. This is the first reported case of a PNGD-like reaction associated with immunotherapy injections. In this article, we discuss this case and summarize the literature related to the diagnosis and management of PNGD, as well as other injection site reactions related to immunotherapies and experimental vaccines.

Granulomatous Slack Skin With Lung and Esophagus Involvement: A Case Report and Molecular Analysis.

Granulomatous slack skin (GSS) is a rare subtype of mycosis fungoides, and few cases have been known to spread to the blood, lymph nodes, or viscera. We present a case with early dissemination to the lung. A 27-year-old woman, previously healthy, presented with scattered disseminated scaly patches, associated with vulvar and intergluteal firm swelling and groin-skin induration for 1 year. She also reported mild fatigue and breathlessness on moderate exertion. The patient underwent blood tests, skin biopsies, and computed tomography scan. The skin biopsy showed a mildly atypical T-cell lymphoid infiltrate involving the dermis/hypodermis, with focal epidermotropism, associated with a granulomatous infiltrate and elastophagocytosis. The computed tomography scan revealed bilateral ground-glass lung nodular opacities. Positron emission tomography showed an increased signal in the skin and subcutis around the buttocks, inguinal and mediastinal lymph nodes, and lungs. The lung biopsy confirmed a dense T-cell infiltrate with numerous multinucleated giant cells. Subsequently, esophageal involvement was also observed following biopsy. Molecular analyses demonstrated identical T-cell clones in the skin and lung. After 6 cycles of chemotherapy/localized external radiotherapy, the patient had a partial skin response and stable lung disease. A preferred diagnosis of GSS with systemic spread was made based on clinical/histologic/molecular findings, after considering granulomatous mycosis fungoides and peripheral T-cell lymphoma, not otherwise specified. This case highlights the frequent diagnostic difficulty in distinguishing GSS from an inflammatory granulomatous dermatitis. Pulmonary and esophageal involvements are rare in GSS, and the simultaneous presentation of characteristic cutaneous GSS with systemic disease poses an additional classification challenge.

Mycobacterium welchii Vaccine Granuloma – A Cautionary Tale

Background: Mycobacterium welchii (Mycobacterium w) vaccine was one of the many strategies used to both treat and prevent coronavirus disease 2019 (COVID-19) infection. We report the results of a retrospective analysis of 15 cases with vaccine-site granulomas after administration of prophylactic Mycobacterium w vaccine as part of a trial for COVID-19 and our experience in managing those cases. Methods: This was a retrospective analysis of 15 patients with vaccine-site granulomas who were given the vaccine as a prophylactic measure as part of a trial with informed consent. Results: The mean average age of cases was 37 and the male-to-female ratio was 1:0.87. All of the patients developed erythematous tender nodules over the injection sites within a month of receiving the inoculations. Mycobacterial cultures and cartridge-based nucleic acid amplification tests yielded negative results. Skin biopsy revealed granulomatous dermatitis with acid-fast bacilli positivity. A diagnosis of noninfective granulomatous dermatitis was made. Treatment started with analgesics and anti-inflammatory agents. Systemic antibiotics were required in 9/15 patients. Patients are being followed up with no reported recurrence till date. Conclusion: The possibility of injection-site granuloma should be taken into the risk–benefit analysis for the administration of Mycobacterium w vaccine and the patients should be counseled as such. Patients with persistent ulceration respond to combinations of doxycycline, ofloxacin, and clarithromycin.

An Interesting Case of Blau Syndrome – A Rare Autoinflammatory Disease

Abstract Blau syndrome is an autosomal dominant, autoinflammatory disease. It typically presents in early childhood with a triad of granulomatous uveitis, symmetrical arthritis, and dermatitis. A 6-year-old child presented to us after being diagnosed with granulomatous uveitis. Examination revealed bilateral boggy wrist swellings. Suspecting Blau syndrome, clinical exome sequencing was performed, which reported a mutation in the NOD2/CARD15 gene confirming the diagnosis. Our case demonstrates that the classical triad of this disease may not be present in all patients, and all features may not occur simultaneously. A high index of suspicion is required for the diagnosis of this rare disease.

Reactive Granulomatous Dermatitis: A Descriptive Study of 10 Patients.

Reactive granulomatous dermatitis (RGD) is a rare and misunderstood skin disorder. It includes interstitial granulomatous dermatitis and palisaded neutrophilic and granulomatous dermatitis: 2 entities of the same spectrum. Multiple associations are described with RGD in the literature, including autoimmune diseases, malignancy, and drugs. To report and describe the suspected associations with RGD at the time of diagnosis and in the following year. We retrieved and described cases of RGD confirmed by skin biopsy and clinicopathologic correlation. All patients were evaluated in the Centre Hospitalier Universitaire de Québec-Université Laval between January 2000 and December 2020. Collected data include the systemic diseases (autoimmune disease, malignancy) and suspected drugs, in addition to the clinical presentation and prescribed treatments. Out of the 10 patients with RGD, 7 patients were known to have an autoimmune disease at the time of diagnosis. They either had inflammatory arthritis (3/10) or inflammatory bowel disease (4/10). There was a clinical suspicion of a possible association with a tumor necrosis factor (TNF) inhibitor in 2 of these 7 patients. Among the 3 patients with idiopathic RGD at the time of diagnosis, 1 patient developed a high-grade B-cell lymphoma 6 months later. There was no new association identified in the following year for patients with a known autoimmune condition. This descriptive study supports RGD and its previously described systemic associations, particularly autoimmune diseases, malignancy, and certain drugs (specifically TNF inhibitors). The majority of patients already had one of these associations identified at the time of histopathological diagnosis.

Granulomatous dermatitis post Mycobacterium Indicus Pranii (MIP) vaccine in severe covid-19 infection: an exaggerated hypersensitivity phenomenon

Granulomatous dermatitis post Mycobacterium Indicus Pranii (MIP) vaccine in severe covid-19 infection: an exaggerated hypersensitivity phenomenon

Three cases of sterile granulomatous dermatitis and lymphadenitis in a female Golden Retriever and her litter of pups

Three cases of sterile granulomatous dermatitis and lymphadenitis in a female Golden Retriever and her litter of pups

Clinicohistopathological Concordance of Cutaneous Granulomatous Disorders at a Tertiary Care Hospital in Northern India: A Cross-sectional Study

Introduction: Granulomatous inflammatory pattern is a chronic inflammation with a limited number of possible conditions that cause it. Therefore, for treatment purposes, its diagnosis is mandatory. The overlapping clinical and histological features of granulomatous dermatitis demand a proper system of classification. The aetiology, histopathological granuloma patterns, and the morphology of various skin lesions can be informative and supportive towards their diagnosis. Aim: To determine the distribution of various cutaneous granulomatous disorders in the demographical region and their causative agents. Materials and Methods: This cross-sectional study was conducted in the Histopathology section of the Department of Pathology, Government Medical College, Jammu and Kashmir, India over a period of five years (1st November 2014-31st October 2019) involving a prospective and retrospective analysis of 1,150 skin biopsies. A clinical diagnosis of Infectious Cutaneous Granulomatous Disorders (IGDS) was made in 560 cases included in the study. Out of 560 cases, the histopathological diagnosis of IGDS was confirmed in 361 cases. The aetiology and granuloma histology were studied. A clinicopathological agreement was established with the kappa test. Results: Leprosy was the most common histopathological diagnosis, with 343 out of 361 cases (95.01%), followed by tuberculosis with 9 out of 361 cases (2.49%). Leprosy subtypes included Lepromatous Leprosy (LL) in 75 cases (21.87%), followed by Borderline Tuberculoid (BT) in 71 cases (20.70%). Among the nine cases of cutaneous tuberculosis, Lupus Vulgaris (LV) was found in five cases (55.56%), followed by Scrofuloderma (SD) in three cases (33.33%), and Tuberculosis Cutis Orificialis (TCO) in one case (11.11%). The cases of leprosy showed maximum clinicopathological concordance in 343 cases (68.33%), with the BT type being the most concordant with the clinical diagnosis at 30 out of 64 cases (46.88%). A statistical analysis of kappa was applied to the subtypes of leprosy, and the observed kappa value was 0.3439, indicating agreement between histology and clinical diagnosis. Conclusion: Histopathological examination is the gold standard for diagnosing, categorising, and determining clinicopathological concordance of cutaneous granulomatous lesions. The wide spectrum of clinical differentials can be narrowed down. Although the importance of clinical examination and ancillary techniques for confirming the diagnosis cannot be denied, considering all aspects together can lead to a final conclusive diagnosis.

Challenging diagnosis of the spectrum of reactive granulomatous dermatitis: two case reports and literature review

Challenging diagnosis of the spectrum of reactive granulomatous dermatitis: two case reports and literature review

Herpes Zoster Granulomatous Dermatitis: A Rare but Memorable Complication

There have been reports of benign and cancerous cutaneous reactions developing at the site of resolved herpes zoster weeks to years after the acute infection. This case study describes a 71-year-old male patient with herpes zoster granulomatous dermatitis, a manifestation of postherpetic isotopic response. His medical history was significant for Graves' disease and chronic myelomonocytic leukemia. After presenting to the emergency department, he was diagnosed with herpes zoster generalisatus. Approximately two months after receiving treatment for herpes zoster, multiple firm subcutaneous nodules appeared on his neck. An excisional biopsy was performed to rule out leukemia cutis. The specimen displayed extensive dermal lymphohistiocyte infiltration, marked by central necrosis and atypical T cells. Tests for tuberculosis and leukemia were negative. At follow-up, an excisional biopsy of the recurrent neck nodules confirmed diffuse dermal infiltration and central necrosis. Based on the clinical and pathological findings, he was diagnosed with herpes zoster granulomatous dermatitis. He was administered systemic and topical steroid therapy over one month, after which the lesions and associated symptoms improved. Wolf's isotopic response refers to the occurrence of a new skin disease at the site of an already healed, unrelated skin disease. This phenomenon is frequently overlooked—especially following herpes zoster. Healthcare practitioners should know Wolf's isotopic response to ensure accurate diagnosis and avoid potential oversight of malignant diseases.

Granulomatous dermatitis caused by Exserohilum mcginnisii infection in a cow.

A 5-y-old, Piedmontese cow had a 4-mo history of ongoing development of skin masses. This was the only cow affected in a herd of 20 cows. Up to 12, hairless, red-to-black, raised nodules-to-plaques were distributed along the dorsum and tail head. Biopsies were taken for histopathology and ancillary testing. An ulcerated skin section contained dermal infiltrates of eosinophils, plasma cells, neutrophils, macrophages, lymphocytes, and multinucleate giant cells, and pyogranulomas. Fungal hyphae were seen within the dermis, multinucleate giant cells, and pyogranulomas. In pyogranulomas, fungi were surrounded by a Splendore-Hoeppli reaction. Dematiaceous (pigmented) hyphae were rarely observed with H&E-stained and unstained (cleared and mounted) sections, but stained well with a Fontana-Masson stain. Exserohilum mcginnisii was identified by fungal culture, followed by PCR assay and sequencing. Exserohilum is a dematiaceous fungus that causes disease in humans and rarely in animals. The use of unstained sections and Fontana-Masson stain are important to demonstrate pigment because dematiaceous fungi have little melanin and appear as hyaline hyphae histologically. PCR assay and sequencing aid in the differentiation and classification of fungal species. To our knowledge, E. mcginnisii dermal granulomas have not been reported previously in cattle.