Streptococcus bovis infection of the central nervous system: report of two cases and review.

Streptococcus bovis is an uncommon cause of meningitis and subdural empyema. We report one case each of meningitis and subdural empyema in which S. bovis biotype II was isolated from both the spinal fluid and blood. In one case, the organisms were seen on a gram-stained preparation of cerebrospinal fluid. The first patient presented with gastrointestinal symptoms of unknown etiology, was immunosuppressed, and recovered. The second patient presented with syncope, developed a subdural empyema, and died; at autopsy, a colonic adenoma was found. A review of the English-language literature revealed only 14 previously reported cases of meningitis due to S. bovis and no cases of subdural empyema due to S. bovis. These cases indicate the importance of complete laboratory identification of specific organisms and confirm the need for a thorough neurological examination and search for underlying gastrointestinal disease in cases of S. bovis infection.

Horseshoe kidney is associated with an increased relative risk of primary renal carcinoid tumor.

PURPOSE: Carcinoid tumor is a rare neoplasm of the kidney with an unknown histogenesis. Of only 31 cases previously reported in the literature 4 arose within horseshoe kidneys. We report a case of primary carcinoid tumor arising within a horseshoe kidney and discuss the unique insight it provided into the pathogenesis of this tumor. MATERIALS AND METHODS: We reviewed in detail all 31 reported cases of renal carcinoid tumor and, using reported incidence rates of horseshoe kidney, we calculated the relative risk of renal carcinoid tumor arising within a horseshoe kidney. Immunohistochemical staining for neuroendocrine related markers was performed on tissue sections from the present carcinoid tumor, the adjacent kidney and 5 control samples of normal renal parenchyma. RESULTS: Of the reported tumors 15.6% occurred in horseshoe kidneys, yielding a calculated relative risk of 62. The present tumor was multifocal, arising from the wall of a cystic lesion and possibly representing a dilated calix within the isthmus. Intestinal epithelium lining the cyst cavity exhibited multifocal neuroendocrine cell hyperplasia with an immunohistochemical profile identical to that of the carcinoid tumor cells. CONCLUSIONS: The relative risk of renal carcinoid tumor developing in a horseshoe kidney is markedly greater than that for Wilms tumor or transitional cell carcinoma. The clinical course of renal carcinoid tumor arising within a horseshoe kidney appears to be more benign than that of the nonhorseshoe variant. Our observations support the hypothesis that renal carcinoid tumors may arise from neuroendocrine cells within foci of metaplastic or teratomatous epithelium within the kidney.

Transitional cell carcinoma in a tuberculous kidney: case report and review of the literature.

Transitional cell carcinoma of the renal pelvis is uncommon. Tuberculosis and cancer manifesting in the same kidney is even more unusual. To our knowledge we report the first case of tuberculosis and transitional cell carcinoma occurring in the same kidney.

Solitary brainstem metastasis: comparisons of X-ray computed tomography and magnetic resonance imaging to pathology.

A case of solitary brainstem metastasis from a bronchogenic adenocarcinoma is presented. X-ray computed tomography, magnetic resonance imaging, and specimens obtained at autopsy are compared. T2 weighted magnetic resonance images provided evidence for the diagnosis of a diffusely infiltrating process, whereas T1 weighted images demonstrated a clearly defined, well demarcated tumor. Contrast enhanced computed tomography supported evidence obtained from the T1 weighted image. At autopsy, the tumor was a well circumscribed pontine metastasis with surrounding edema. The importance of distinguishing between T1 and T2 weighted images is crucial for establishing a correct diagnosis and for instituting proper therapy. In contrast to some reports, we found that the T2 weighted image was misleading in regard to defining the extent of tumor. We conclude that both images must be considered together to provide an accurate diagnostic estimate.