Pure Bullous Pyoderma Gangrenosum, a Challenging Clinico-Pathological Diagnosis: Critical Literature Review with Emphasis on Diagnostic Criteria.

Pyoderma gangrenosum (PG) is an uncommon, idiopathic, neutrophilic dermatosis characterised by large necrotic ulcers. Occasionally, patients develop atypical presentations, including pustular, bullous, and vegetative lesions. Bullous pyoderma gangrenosum (BPG) is considered an extremely rare form. We describe a case of BPG in a 76-year-old man, with active oncological history, including a recent diagnosis of hairy cell leukemia. Diagnosis of PG was delayed because of atypical clinical presentation that mimicked necrotising fasciitis. The patient was treated with diverse intravenous antibiotics and several surgical procedures. The suspicion of neutrophilic dermatosis arose from the histopathological studies. In the setting of mandatory clinico-pathological correlation, the aim of this report is to point out the morphological characteristics that allow recognition of this uncommon variant of pyoderma gangrenosum.

Lymphoplasmacytic lymphoma and marginal zone lymphoma involving bone marrow: A diagnostic dilemma. Useful clinicopathological features to accurate the diagnosis.

Lymphoplasmacytic lymphoma (LPL) and marginal zone lymphoma (MZL) frequently infiltrate the bone marrow with similar histologic and immunohistochemical characteristics posing diagnostic problems. Bone marrow biopsy specimens from 25 LPL and 16 MZL have been studied, correlating with clinical, laboratory parameters and the MYD88_p.L265P mutation. Paratrabecular and interstitial infiltration pattern, serum IgM paraprotein levels, and MYD88_p.L265P mutation were significantly more frequent in LPL. Nodular or intrasinusoidal pattern with lymphocytosis and splenomegaly were associated with MZL diagnosis. Different clinical and histological parameters should be collected when LPL or MZL is suspected in bone marrow biopsy specimens.

Fulminant Sepsis Caused by Leclercia adecarboxylata in a Premature Neonate: Case Report and Review of the Literature.

Hospital-acquired infections are especially evident in premature infants because of prolonged stays and the need for invasive procedures. Leclercia adecarboxylata is an uncommon emerging Gram-negative bacterium that has been described in catheter and noncatheter-related infections, immunocompromised patients and less frequently affecting healthy subjects. We report a case with a postmortem diagnosis of a 24-week-old premature neonate who died as a complication of nosocomial sepsis related to an infection by L. adecarboxylata. Although the cases of L. adecarboxylata infection in children have been rarely reported, this case appears to be the first in which an infection by L. adecarboxylata is accompanied by focal spontaneous ileal perforation.

Severe Acute Respiratory Syndrome Coronavirus 2 Spreads to Lymph Nodes and Strongly Expands CD4+ Effector Memory RA Cells in a Patient With Mild Coronavirus Disease 2019.

A woman with mild coronavirus disease 2019 developed cervical adenopathy, being diagnosed of Epstein-Barr virus infectious mononucleosis. We performed fine needle aspiration, and demonstrate that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is found in lymph nodes even in mild disease along with a strong expansion of terminally differentiated effector memory CD4+ T cells, a cell population that is practically absent in lymph nodes.