Non-infectious granulomatous dermatoses

Diagnostic challenges in cutaneous leishmaniasis due to atypical Leishmania infantum: pathologists' insights from re-emergence zones

Background

Leishmaniasis, a parasitic infection affecting both humans and animals, is increasingly spreading across Mediterranean and European regions, largely driven by human migration and environmental changes. In countries like Türkiye and across Europe, which have seen large influxes of migrants, the incidence of cutaneous leishmaniasis (CL) is rising, with cases now appearing in cities where the disease was previously undocumented. In these previously non-endemic areas, physicians unfamiliar with the characteristic lesions may misdiagnose CL, particularly in cases with only cutaneous manifestations. This study aims to evaluate the impact of re-emerging CL on the routine diagnostic practices of pathologists in Türkiye, by retrospectively reviewing cases.

Methods

We conducted a retrospective analysis of CL cases diagnosed between 2013 and 2022 at a single pathology center in Türkiye, covering multiple provinces. Twelve cases of CL were identified and analyzed based on clinical presentation, pre-diagnosis, histopathological findings, and molecular diagnostics. DNA extraction and PCR were performed on paraffin-embedded tissue samples to identify the Leishmania species involved.

Results

Out of the twelve CL cases reviewed, seven exhibited morphological findings strongly suggestive of CL (MFSS of CL), warranting further microbiological evaluation. All patients presented with non-healing skin lesions characterized by central ulceration, crater-like formations, or papulonodular lesions. Notably, CL was included in the clinical pre-diagnosis in only 58.3% of cases, while it was not considered in the remaining 41.7% of cases. Clinicians initially pre-diagnosed skin tumors in six cases (50%), four of which led to wide surgical excision. Histopathological examination in all cases revealed chronic or mixed (acute/chronic) inflammation, predominantly rich in histiocytes. To further investigate the role of Leishmania species in the pre-diagnosis, DNA extraction and PCR were performed on paraffin-embedded tissue samples, identifying L. infantum as the causative agent in 10 cases and L. major in two cases. Notably, L. infantum was the causative agent in all five cases initially misdiagnosed as skin tumors, which were also associated with a granulomatous type of chronic inflammation.

Foreign body granulomas mimic peritoneal dissemination caused by incarcerated femoral hernia perforation: A case report

BACKGROUND

Foreign body granuloma (FBG) is a well-known type of granulomatous formation, and intraabdominal FBG (IFBG) is primarily caused by surgical residues. Multifocal IFBGs caused by gastrointestinal perforation is an extremely rare and interesting clinicopathological condition that resembles peritoneal dissemination. Here, we present a case of IFBGs mimicking peritoneal dissemination caused by bowel perforation and describe the value of intraoperative pathological examinations for rapid IFBG diagnosis.

CASE SUMMARY

An 86-year-old woman with an incarcerated femoral hernia was admitted to the hospital and underwent operation. During the operation, the incarcerated ileum was perforated during repair due to hemorrhage necrosis, and a small volume of enteric fluid leaked from the perforation. The incarcerated ileum was resected, and the femoral hernia was repaired without mesh. Four months later, a second operation was performed for an umbilical incisional hernia. During the second operation, multiple small, white nodules were observed throughout the abdominal cavity, resembling peritoneal dissemination. The results of peritoneal washing cytology in Douglas’ pouch and the examination of frozen nodule sections were compatible with IFBG diagnosis, and incisional hernia repair was performed.

CONCLUSION

IFBGs can mimic malignancy. Intraoperative pathological examinations and operation history are valuable for the rapid diagnosis to avoid excessive treatments.

Immune-Mediated Dermatoses in Patients with Haematological Malignancies: A Comprehensive Review

Haematological malignancies induce important alterations of the immune system, which account for the high frequency of autoimmune complications observed in patients. Cutaneous immune-mediated diseases associated with haematological malignancies encompass a heterogeneous group of dermatoses, including, among others, neutrophilic and eosinophilic dermatoses, autoantibody-mediated skin diseases, vasculitis and granulomatous dermatoses. Some of these diseases, such as paraneoplastic pemphigus, are associated with an increased risk of death; others, such as eosinophilic dermatoses of haematological malignancies, run a benign clinical course but portend a significant negative impairment on a patient’s quality of life. In rare cases, the skin eruption reflects immunological alterations associated with an unfavourable prognosis of the associated haematological disorder. Therapeutic management of immune-mediated skin diseases in patients with haematological malignancies is often challenging. Systemic corticosteroids and immunosuppressive drugs are considered frontline therapies but may considerably augment the risk of serious infections. Indeed, developing a specific targeted therapeutic approach is of crucial importance for this particularly fragile patient population. This review provides an up-to-date overview on the immune-mediated skin diseases most frequently encountered by patients with onco-haematological disorders, discussing new pathogenic advances and therapeutic options on the horizon.

Pathogenetic mechanism of oral granulomatous diseases: An update

Oral granulomatous diseases are an intriguing group of lesions characterized by granuloma formation. Mechanisms of granuloma formation differ from disease-to-disease. This article provides an insight into common granulomatous pathogenic mechanisms involving these lesions including immunodeficient states. Understanding various pathogenic mechanisms underlying various granulomatous conditions affecting oral tissues which mainly revolve around inflammatory cells such as macrophages, T lymphocytes, and genetic mutations might aid in devising treatment modalities without having significant side-effects or morbidity in affected subjects.