Multiple pulmonary nodules caused by zygomycosis in a patient without predisposing factors

Differential diagnosis of pulmonary sarcoidosis: a review

Diagnosing pulmonary sarcoidosis raises challenges due to both the absence of a specific diagnostic criterion and the varied presentations capable of mimicking many other conditions. The aim of this review is to help non-sarcoidosis experts establish optimal differential-diagnosis strategies tailored to each situation. Alternative granulomatous diseases that must be ruled out include infections (notably tuberculosis, nontuberculous mycobacterial infections, and histoplasmosis), chronic beryllium disease, hypersensitivity pneumonitis, granulomatous talcosis, drug-induced granulomatosis (notably due to TNF-a antagonists, immune checkpoint inhibitors, targeted therapies, and interferons), immune deficiencies, genetic disorders (Blau syndrome), Crohn's disease, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and malignancy-associated granulomatosis. Ruling out lymphoproliferative disorders may also be very challenging before obtaining typical biopsy specimen. The first step is an assessment of epidemiological factors, notably the incidence of sarcoidosis and of alternative diagnoses; exposure to risk factors (e.g., infectious, occupational, and environmental agents); and exposure to drugs taken for therapeutic or recreational purposes. The clinical history, physical examination and, above all, chest computed tomography indicate which differential diagnoses are most likely, thereby guiding the choice of subsequent investigations (e.g., microbiological investigations, lymphocyte proliferation tests with metals, autoantibody assays, and genetic tests). The goal is to rule out all diagnoses other than sarcoidosis that are consistent with the clinical situation. Chest computed tomography findings, from common to rare and from typical to atypical, are described for sarcoidosis and the alternatives. The pathology of granulomas and associated lesions is discussed and diagnostically helpful stains specified. In some patients, the definite diagnosis may require the continuous gathering of information during follow-up. Diseases that often closely mimic sarcoidosis include chronic beryllium disease and drug-induced granulomatosis. Tuberculosis rarely resembles sarcoidosis but is a leading differential diagnosis in regions of high tuberculosis endemicity.

[Disseminated mucormycosis in immunocompetent patients: A disease that also exists]

Mucormycosis is usually an acute angioinvasive infections, which leads to non-suppurative necrosis and significant tissue damage. It represents 1.6% of all the invasive fungal infections and predominates in immunosuppressed patients with risk factors. Incidence has been significantly increased even in immunocompetent patients. Due to finding a case of disseminated mucormycosis caused by Rhizomucor pusillus in a young immunocompetent patient, a systematic review was carried out of reported cases in PubMed of mucormycosis in immunocompetent adults according to the main anatomic locations, and especially in disseminated cases. A review of the main risk factors and pathogenicity, clinical manifestations, techniques of early diagnosis, current treatment options, and prognosis is presented. Taxonomy and classification of the genus Mucor has also been reviewed.

Recurrent pulmonary mucormycosis after lobectomy in a non-smoking patient without predisposing risk factors

Pulmonary mucormycosis is a very rare clinical condition in patients without underlying risk factors. A limited number of cases have been reported in predominantly elderly patients; history of smoking appears to be a common feature. A case of non-smoking male who developed pulmonary mucormycosis with the longest reported follow-up is presented. In addition, this is also the first reported case with disease recurrence after lobectomy (two years) in an immunocompetent host. Treatment with an additional lobectomy and amphotericin B was successful in this patient.

Case report. Localized pulmonary zygomycosis without pre-existing immunocompromised status

Pulmonary zygomycosis rarely occurs without pre-existing immunocompromised disease. A 72-year-old male was found to have a nodular shadow (3 cm x 4 cm) in the right S8 and S9 on a chest X-ray. Right lower lobectomy was performed and histological examination of the resected material demonstrated pulmonary zygomycosis. Hyphae stained positively not only with Grocott-Gomori methenamine silver staining, but also with an anti-Rhizopus oryzae polyclonal antibody.