Disseminated Nasal subtype Extranodal NK/T-cell lymphoma and its diagnostic difficulties in antemortem biopsies

ABSTRACT Extranodal NK/T- cell lymphoma (ENKTCL) is an aggressive lymphoma driven by Epstein-Barr virus (EBV) infection in genetically susceptible individuals. It was historically called a lethal midline granuloma. Due to the angio-destructive nature of ENKTCL, lymphoma cells are often accompanied and masked by necrosis and dense inflammation in the biopsy. Further, the biopsy may show vasculitis, which can mimic granulomatosis with polyangiitis. Due to these masquerades, ENKTCL is often misdiagnosed in the biopsy. Several biopsies may be required to establish the diagnosis. We describe the clinical course and autopsy findings of a young female who presented with a hard-palate ulcer. Antemortem biopsies failed to establish the diagnosis. The autopsy revealed an advanced nasal subtype of Extranodal NK/T-cell lymphoma with dissemination to the kidneys, adrenals, liver, spleen, and small intestine.

Myocardial infarction due to septic thromboembolism in chronic rheumatic heart disease

ABSTRACT Chronic rheumatic heart disease (RHD) is the most troublesome complication of rheumatic fever. Extensive valvular scarring and ventricular remodeling due to pressure and volume overload occur in chronic RHD. Deformed valves are at potential risk for developing infective endocarditis (IE) with further systemic embolism. We hereby describe a case of a patient diagnosed with chronic rheumatic heart disease and severe ventricular dysfunction, planned for aortic valve replacement. The patient developed septic shock during a hospital stay. The autopsy revealed infective endocarditis in the aortic valve with septic thromboembolism in the peripheral branches of the coronary artery and early multifocal myocardial infarction changes.

Rickettsia conorii infection with fatal complication

ABSTRACT Rickettsial diseases (RD) are a group of endotheliotropic infectious diseases caused by different species of genera Rickettsia. RD are not an uncommon disease and may be misdiagnosed during the evaluation of acute febrile illness due to a lack of reliable serological marker and diagnostic culture methods. Clinical manifestation of RD varies from febrile illness with rashes and myalgia to fatal complications such as shock and respiratory failure. We describe a case of a young male who presented initially with acute febrile illness, followed by shock and respiratory failure, and unfortunately succumbed to death. A post-mortem examination showed histological features of endotheliotropic infection, such as interstitial / perivascular edema in various organs and noncardiogenic pulmonary edema (suggesting increased vascular permeability) and evidence of vasculitis in the lung, liver, and intestines. Molecular studies performed from lung, liver, and kidney tissue confirm the diagnosis of spotted fever group rickettsial disease due to Rickettsia conorii.

Non-infectious thrombotic endocarditis associated with chronic rheumatic heart disease and disseminated tuberculosis

Rheumatic heart disease is still common in developing countries and requires prompt intervention to prevent chronic complications. Vegetations in rheumatic heart disease might be due to acute episodes of rheumatic fever itself or due to either infective endocarditis (IE) or Non-infectious thrombotic endocarditis (NITE). Each form of vegetations has specific pathological characteristics on gross and microscopic examination. However, clinically IE and NITE may have overlapping signs and symptoms. A chance of misdiagnosis of NITE as culture-negative infective endocarditis is higher if the former present with infective symptoms like fever. NITE of valves can be due to underlying associated malignant neoplasm, particularly mucinous adenocarcinoma, pneumonia, cirrhosis, autoimmune disorders, and hypercoagulable state. The coexistence of tuberculosis, non-infectious thrombotic endocarditis and rheumatic valvular heart disease was rarely documented in medical literature. We describe a case of chronic rheumatic heart disease with vegetations in the posterior mitral valve leaflet, treated as culture-negative infective endocarditis, which, at autopsy, reveals the presence of Nonbacterial thrombotic endocarditis vegetation over calcified, fibrosed mitral valve leaflets and associated disseminated tuberculosis along with classic pathological sequela findings of chronic rheumatic mitral valvular heart disease in lungs and liver.

SMILE-like lesion in the anal canal

Stratified mucin-producing intraepithelial lesion (SMILE) is an intraepithelial lesion with overlapping features of the high-grade squamous intraepithelial lesion (HSIL) and adenocarcinoma in situ (AIS). Currently, it is well described in the cervix. We present a case showing similar SMILE-like lesions in the polypectomy specimen from the anal canal along with invasive adenocarcinoma components. This lesion showed an immuno-profile characteristic of a SMILE lesion described in the cervix, such as p63 negativity, high ki67 index, and nuclear positivity for p16. It might be arising from the Human papillomavirus prone transitional region of the anal canal as described in the cervix. However, we could not assure this association and etiological link due to insufficient material in the formalin-fixed paraffin-embedded block. Notwithstanding, we strongly suggest that the HPV is the main driver for this SMILE-like lesion similar to what is described in the cervix. To our knowledge, this is the first case report of a SMILE lesion in the anal canal. Further studies will be required to elucidate the underlying pathogenetic mechanism of SMILE-like lesions described in the anal canal.