Cytomorphologic and immunocytochemical characterization of pediatric pleuropulmonary blastoma with a comprehensive review of the literature.

INTRODUCTION: Pleuropulmonary blastoma (PPB) is a rare, aggressive, primary intrathoracic malignancy typically seen in infancy and early childhood. Accurate distinction from congenital cystic lung lesions is crucial due to significant prognostic and therapeutic differences. Cytologic features have rarely been described. Establishing a cytodiagnosis is challenging owing to its rarity, lack of awareness, and multiple morphologic mimics. MATERIALS AND METHODS: This was a retrospective study conducted over 8 years. The histopathology and cytopathology databases were searched for all pediatric PPB cases. The corresponding cytologic samples were reviewed to identify characteristic features that can help distinguish PPB from its mimics. RESULTS: There was a total of six cases of pediatric PPB reported during the study period. Of these, four (66.7%) presented as intrathoracic, and two (33.3%) as pleural-based masses. Cytology smears showed discretely scattered and perivascular arrangements of round-oval tumor cells with background eosinophilic stromal material. The tumor cells were mildly pleomorphic (n = 3) with round nuclei, fine chromatin, inconspicuous nucleoli, and scanty cytoplasm; however, three cases showed marked anaplasia, and one each showed necrosis and rhabdoid differentiation. On immunocytochemistry (4/6), these were positive for vimentin and desmin and negative for WT1, chromogranin, SALL4, cytokeratin, CD45, and CD99. FISH (1/6) did not show N-Myc amplification. CONCLUSIONS: Knowledge of the characteristic cytomorphological and immunocytochemical features of PPB is vital to establish a prompt and accurate cytodiagnosis with appropriate clinicoradiologic correlation.

Rickettsia conorii infection with fatal complication.

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.

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.