Relapsing Multiple Myeloma Presenting as Cardiac Tamponade and Obstructive Uropathy.

Cardiac tamponade is a rare manifestation of relapsing extramedullary multiple myeloma and portends poor prognosis. No cases of cardiac tamponade with co-occurring renal obstruction from plasmacytoma have been reported in the literature, making this case a unique presentation of relapsing multiple myeloma. The presence of known malignancy should not limit our differential diagnosis when evaluating patients with signs of cardiac tamponade.

Blastic Plasmacytoid Dendritic Cell Neoplasm: A Case Series and Review.

ABSTRACT: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy that frequently has cutaneous manifestations. The diagnosis can be a challenge because of its heterogenous clinical presentation, ranging from a brown or violaceous solitary nodule or patch to mixed, disseminated lesions. Furthermore, BPDCN tumor cells express immunohistochemical markers in common with acute myeloid leukemia, which can lead to misdiagnosis. Timely diagnosis requires awareness of its cutaneous manifestations and unique histopathology and immunophenotype. We present a case series of patients diagnosed with BPDCN and review the cutaneous and histopathologic characteristics of this uncommon entity.

What lies beneath: Cutaneous involvement of mantle cell lymphoma underlying an insect-bite-like reaction.

Mantle cell lymphoma (MCL) is an uncommon subtype of mature B-cell non-Hodgkin lymphoma characterized by specific morphologic, immunophenotypic, and genetic characteristics, namely the t(11;14)(q13;q32) chromosomal translocation with resultant cyclin D1 overexpression. MCL has a generally aggressive course and is often widely disseminated at the time of diagnosis. Skin involvement is exceedingly rare and is seldom the first manifestation of MCL. We present a case of MCL in an 84-year-old man with cutaneous involvement as the first manifestation, discovered incidentally after biopsy of a persistent nodule believed to be an insect bite. This case not only serves to raise awareness of the possibility of MCL presenting in the skin but also to point out that MCL can have lesions with both an insect-bite-like reaction and a deeper dermal MCL infiltrate.

Correlation of ELISA method with three other automated serological tests for the detection of anti-SARS-CoV-2 antibodies.

Public health emergency of SARS-CoV-2 has facilitated diagnostic testing as a related medical countermeasure against COVID-19 outbreak. Numerous serologic antibody tests have become available through an expedited federal emergency use only process. This paper highlights the analytical characteristic of an ELISA based assay by AnshLabs and three random access immunoassay (RAIA) by DiaSorin, Roche, and Abbott that have been approved for emergency use authorization (EUA), at a tertiary academic center in a low disease-prevalence area. The AnshLabs gave higher estimates of sero-prevalence, over the three RAIA methods. For positive results, AnshLabs had 93.3% and 100% agreement with DiaSorin or Abbott and Roche respectively. For negative results, AnshLabs had 74.3% and 78.3% agreement with DiaSorin and Roche or Abbott respectively. All discrepant samples that were positive by AnshLabs and negative by RAIA tested positive by all-in-one step SARS-CoV-2 Total (COV2T) assay performed on the automated Siemens Advia Centaur XPT analyzer. None of these methods, however, are useful in early diagnosis of SARS-CoV-2.

An unusual case of cutaneous Waldenström macroglobulinemia with the MYD88 L265P mutation.

Waldenström macroglobulinemia is a lymphoplasmacytic lymphoma with bone marrow involvement and a monoclonal IgM gammopathy. Infiltration of the skin by neoplastic cells is very rare, and it can be difficult to distinguish from marginal zone lymphoma. The MYD88 L265P mutation is strongly associated with Waldenström macroglobulinemia, and it may be helpful in differentiating the two disorders, although the presence of this mutation is not specific, and other factors must be considered when making the final diagnosis. We present a diagnostically challenging case of cutaneous Waldenström macroglobulinemia in which the MYD88 L265P mutation was identified in the skin but not in the bone marrow, due to a low tumor burden.

Perianal Comedones: A Rare Incidental Finding.

Comedones occur when an overproliferation of keratinocytes blocks sebum secretion in a pilosebaceous duct. Comedones have multiple possible etiologies and contributing factors. While comedones are common to acne, they are also seen in occupational exposures and are associated with certain syndromes. We describe a particularly rare case of comedones at the perianus that is not associated with any known exposure or disease and is a rare incidental finding.