Investigating the spectrum of dermatologic manifestations in COVID-19 infection in severely ill patients: A series of four cases.

COVID-19, an infectious disease caused by the novel coronavirus, was initially identified in Wuhan, China, in December 2019. By March 2020, it was declared a pandemic by the World Health Organization. Although most findings have been reported in the lungs, primarily due to catastrophic respiratory decline, other organs, including the skin, are affected. Recent reports have been published describing the clinical spectrum of COVID-19-related lesions. In addition, recent case series have described a subset of these lesions having underlying thrombotic microangiopathy with increased complement activation characterized by increased C4d deposition within the blood vessel walls. Herein, we describe a series of COVID-19-related cutaneous manifestations found at autopsy examination and their underlying histopathologic findings. Although the clinical manifestations seen in these lesions vary widely, the underlying etiology of thrombotic microangiopathy remains consistent and reproducible.

Lentigo maligna melanoma in situ with neurotropism.

Perineural invasion, or neurotropism, is defined by the presence of cancer cells either within the neuronal sheath or found along the nerves. In melanoma, it is most commonly associated with invasive desmoplastic melanoma, a melanoma that is most commonly associated with malignant melanoma in situ, lentigo maligna type. Initially, perineural invasion was included in the reported Breslow thickness; however, recent data suggest that it should not be included. In this report, we describe a case of malignant melanoma in situ, lentigo maligna type, with associated neurotropism in the absence of invasive component.

Novel CTNND2-TERT fusion in a spindle cell liposarcoma.

Soft tissue tumors can be categorized molecularly into two categories: tumors which are known to have recurrent molecular alterations and tumors which do not have consistent recurrent molecular alterations or translocations. These "nontranslocation" associated sarcomas are clinically more aggressive than their more stable counterparts. However, recent advances in RNA sequencing have discovered recurrent novel fusions within the latter group, namely TERT-TRIO fusions. Furthermore, a recent report discovered this fusion in a spindle cell liposarcoma. Our case describes a novel fusion of CTNND2, a neighbor gene of TRIO, and TERT in a spindle cell liposarcoma, and provides further evidence that spindle cell liposarcoma should be a distinct entity from dedifferentiated liposarcoma.

Griscelli Type 2 Syndrome and Hemophagocytic Lymphohistiocytosis: Sisters With the Same Mutation but Different Presentations.

Griscelli syndrome type 2 (GS2) is an autosomal recessive condition associated with the development of hemophagocytic lymphohistiocytosis. GS2 is caused by a gene mutation involving RAB27A, which affects a melanosome anchoring complex in melanocytes and releases cytolytic granules from T cells and natural killer cells. GS2 is known to have immunologic compromise and oculocutaneous albinism. We present the case of 2 sisters who had vastly different phenotypic presentations despite having the same genetic frameshift mutation in the RAB27A gene. Patient 1 presented with seizures and neurological compromise, whereas patient 2 presented with pancytopenia and diarrhea. Both patients developed hemophagocytic lymphohistiocytosis.

Comparison of total protein and enzyme levels in successive regenerations of venom from individual coralsnakes.

Coralsnakes produce highly potent neurotoxic venoms, but little is known about variations in specific enzyme components within a species or from one replenishment of venom to the next within the same animal. Since published studies are often conducted using venom pools from multiple snakes, individual differences are masked and variations among individual snakes and between subsequent venom regenerations from the same snake have rarely been documented. This study involves the analysis and comparison of four successive venom collections from each of nine individual coralsnakes in order to detect these differences. Significant variation was found within the successive re-synthesis of venom components. Even greater differences were observed between the venoms from similar individual snakes. Since studies of variation in enzymatic activity would be significant only if they were above these normal variations, it is important to be aware of these differences. These results suggest the importance of understanding the variations present within and between individuals of the same species when interpreting the potential significance of differences found as the result of genetic, environmental or ecological factors.