Respiratory and enteric cryptosporidiosis in humans.

A 24-year-old homosexual man with acquired immunodeficiency syndrome presented with intractable diarrhea and fever. Examination of a rectal biopsy specimen and stool revealed Cryptosporidium. Approximately 4 months after admission he developed respiratory failure and died. Postmortem examination revealed cryptosporidiosis involving the entire gastrointestinal tract as well as the tracheobronchial tree. To our knowledge, this is one of the rare presented cases of tracheobronchial cryptosporidiosis documented histologically.     

Basaloid carcinoma of the colon arising at the splenic flexure

AIMS: Basaloid carcinomas typically arise in the anal canal and there are only three well-documented cases of this neoplasm reported outside the anal canal, none more proximally than the sigmoid colon. The first occurrence of a basaloid colonic carcinoma arising outside the sigmoid colon, at the splenic flexure, is presented. METHODS AND RESULTS: A splenic flexure mass was resected from a 54-year-old man with a 3-week history of abdominal discomfort, diarrhoea and weight loss. This tumour, like typical anal canal basaloid carcinomas, was composed of islands of basaloid cells with peripheral nuclear palisading; within many islands there was central necrosis and focal squamous differentiation. Ultrastructural and immunohistochemical studies confirmed the basaloid nature and focal squamous differentiation within this neoplasm. Basaloid carcinoma of the anal canal has been associated with human papilloma virus. Using in-situ hybridization, HPV DNA was not detected in this case. CONCLUSIONS: Outside the anal canal, it has been postulated that basaloid colonic carcinomas may arise from cloacogenic embryologic rests, squamous metaplastic epithelium, or totipotential basal cells. The location and pathological findings of this tumour suggest that this rare colonic neoplasm arises from a totipotential basal cell.     

Experimental infection of newly weaned pigs with human and porcine strains of Serpulina pilosicoli.

Cultures of Serpulina pilosicoli 95/1000, isolated from a pig with porcine intestinal spirochetosis (PIS), and S. pilosicoli WesB, isolated from an Aboriginal child with diarrhea, were used to infect 5-week-old newly weaned pigs. Four of 12 pigs infected with strain 95/1000 and 2 of 12 pigs infected with strain WesB became colonized and developed watery, mucoid diarrhea within 2 to 11 days postinfection. Affected pigs all had moderate subacute mucosal colitis, with gross and histological changes similar to those previously reported in both natural and experimentally induced cases of PIS. Silver-stained histological sections of the colon and cecum from affected pigs demonstrated spirochetes within dilated intestinal crypts, where they were associated with neutrophilic exocytosis and mucus secretion. Sections from one pig infected with strain 95/1000 showed large numbers of spirochetes attached by one end to the colonic epithelium, a feature consistent with PIS. This study confirms the role of S. pilosicoli in the etiology of PIS and provides evidence that S. pilosicoli strains of human origin have pathogenic potential in an animal model.     

Microcystic transitional cell carcinoma: a report of 2 cases arising in the renal pelvis

Microcystic transitional cell carcinoma is a rare variant of urothelial carcinoma; to date, it has been described only in the urinary bladder. We report 2 cases of microcystic transitional cell carcinoma arising in the renal pelvis. The first case occurred in a 73-year-old man with a history of superficially invasive transitional cell carcinoma who presented with macroscopic hematuria and anemia. The second case occurred in a 62-year-old woman who had no relevant medical history and presented with hematuria. Computed tomographic scan revealed a tumor of the renal pelvis. In both cases, microscopic examination showed invasive transitional cell carcinoma with prominent cystic features. The cysts were irregular in size and were deeply infiltrative. The cysts were lined by single or multiple layers of cuboidal or flattened cells with minimal cytological atypia. The first patient died of his disease 18 months after presentation. The second patient remained well at her 6-month follow-up examination. Microcystic transitional cell carcinoma is an unusual, deceptively bland variant of urothelial carcinoma, which can mimic benign lesions.     

Campylobacter hyointestinalis associated with human gastrointestinal disease in the United States.

Campylobacter hyointestinalis was isolated from stool specimens of four persons, all of whom were experiencing nonbloody, watery diarrhea. The youngest (8 months of age) and the oldest (79 years of age) individuals were females, and the other two were homosexual men. C. hyointestinalis was the only clinically significant pathogen isolated from stool specimens for three of the individuals. In case 3 (involving a 37-year-old homosexual man), Entamoeba histolytica and Shigella sonnei were also present in the stool. The identification of all C. hyointestinalis strains was made biochemically and confirmed by DNA hybridization. This study documented the isolation of C. hyointestinalis from four patients with diarrhea, and our findings suggest that the clinical significance of Campylobacter species must be expanded to include C. hyointestinalis as a potential cause of human gastrointestinal disease.     

Malakoplakia of liver: Report of two cases

Malakoplakia is an unusual chronic inflammatory condition characterized by the presence of Michaelis-Gutmann bodies. Patients with malakoplakia often have an immunodeficiency state. It is believed that malakoplakia results from a defective macrophage response to phagocytosed bacteria. Malakoplakia most commonly affects the genitourinary tract. Cases confined to the liver are rare, with only five cases described in the literature. We report two cases of malakoplakia of liver; both were incidental autopsy findings. The first case involves a 53-year-old man with systemic lupus erythematosus and chronic refractory pancytopenia who presented with febrile neutropenia. His blood culture was positive for Stenotrophomonas maltophilia and Enterococcus faecium, and he subsequently developed invasive pulmonary aspergillosis. The second case involves a 60-year-old man who presented with a mass in periorbital tissue which, on biopsy, showed inflammation and Treponema-like spirochetes. He died unexpectedly at home. Autopsy revealed adrenal gland chronic inflammation and abscess. Both cases had grossly normal livers with microscopic findings of calcified targetoid structures consistent with Michaelis-Gutmann bodies.     

Isolation of Serpulina pilosicoli from Rectal Biopsy Specimens Showing Evidence of Intestinal Spirochetosis

Histologic evidence of intestinal spirochetosis (IS) was found in 22 of 41 (53.7%) rectal biopsy specimens from homosexual men attending a sexually transmitted diseases clinic. Serpulina pilosicoli was cultured from 11 of the IS-positive biopsy specimens (50%) and from 2 specimens (10.5%) in which spirochetes were not observed. The association between seeing spirochetes in biopsy specimens and isolating S. pilosicoli was statistically significant, clearly indicating that this spirochete is the agent of IS.     

Low-grade mucosa-associated lymphoid tissue lymphoma involving the kidney: report of 3 cases and review of the literature

Low-grade B-cell lymphoma of mucosa-associated lymphoid tissue involving the kidney is rare. We report a series of 3 cases. The first case occurred in an 83-year-old woman who presented with back pain. The second case was a 53-year-old man with a history of sarcoidosis who was found, in the course of evaluation of sarcoidosis, to have a right renal mass. The third case occurred in a 72-year-old man who had a history of periorbital mucosa-associated lymphoid tissue lymphoma and had been treated with surgery and radiation 1 year prior to this presentation. Histologically, all 3 patients showed infiltrate of uniform small-to-medium-sized lymphocytes with irregular nuclear contours and abundant cytoplasm resembling centrocytes or monocytoid lymphoid cells. The first patient received chemotherapy without complications. The second patient underwent a partial nephrectomy and was asymptomatic at the subsequent follow-up. The third patient developed a pulmonary embolism following nephrectomy, and further follow-up is not available.     

Two cases of epithelioid angiosarcoma involving the thyroid and a brief review of non-Alpine epithelioid angiosarcoma of the thyroid

Epithelioid angiosarcoma involving the thyroid is a rare entity, more often described in the Alpine region. Two cases of epithelioid angiosarcoma that affected the thyroid in patients from a non-Alpine location were diagnosed during a 10-year period in our department. The first case occurred in an 89-year-old Chinese man with a history of longstanding goiter, whereas the second case involved a 74-year-old Chinese man with a history of angiosarcoma of the scalp. On histologic examination, both thyroid tumors were composed of plump epithelioid cells with vesicular chromatin and prominent nucleoli, forming vascular structures and solid sheets. Positive staining for CD31 and factor VIII-related antigen confirmed endothelial differentiation in both cases. Both patients died within 5 months following the diagnosis of thyroid disease. The relationship of the scalp angiosarcoma and thyroid disease of the second patient is unclear. A brief review of non-Alpine primary thyroid epithelioid angiosarcoma is presented.     

Campylobacter cryaerophila isolated from a human.

Campylobacter cryaerophila was recovered from a single stool specimen of a 35-year-old homosexual man who presented with intermittent diarrhea for 4 to 6 months. The isolate was identified as C. cryaerophila by using biochemical reactions and confirmed by DNA-DNA hybridization and gas-liquid chromatograph profiles. The base composition of DNA of the isolate was found to be 31.1 +/- 1 mol% (G+C). C. cryaerophila was previously reported to be associated with bovine and porcine abortions in animals. We believe this is the first report of recovery of C. cryaerophila from human stool.     

Leiomyoma of the male urethra: a case report and review of the literature

We describe the case of a 48-year-old quadriplegic black man with history of C4-C5 cervical spine and cord injury secondary to a fall, who presented to the University of Cincinnati Medical Center Urology Service with obstructive symptoms at urination. A bulbous urethral stricture was diagnosed and subsequently resected with primary urethral reanastomosis. On pathologic examination, the surgical specimen contained an epithelioid leiomyoma at the site of the urethral stricture. Although leiomyomas of the female urethra are relatively common, we identified only 2 previously reported cases of leiomyomas of the male urethra in the English-language medical literature. To the best of our knowledge, we describe the third case of leiomyoma of the male urethra, the first of the epithelioid type.     

Colonic adenocarcinoma metastasizing as a germ cell neoplasm: a case report and review of the literature

Mixed tumors of the gastrointestinal tract, including both adenocarcinoma and germ cell neoplasm, have been reported infrequently. In the colon, only 9 cases, to our knowledge, have been described in the English-language literature. This is the case of a 29-year-old man with an unsuspected mixed colonic neoplasm that metastasized as the germ cell component.     

Rectal syphilis mimicking histiocytic lymphoma

Homosexuality is being recognized with increasing frequency in the United States, and the physician must be knowledgeable of the presentations of venereal infection in this population. A 23-year-old man who denied homosexuality presented with a rectal mass and diffuse adenopathy. Biopsy of the mass was interpreted as histiocytic lymphoma. Subsequent serology had positive results for syphilis. Further questioning revealed a history of anorectal intercourse, and special stains of the mass revealed spirochetes. Syphilis must be considered in any young patient presenting with a rectal mass, regardless of the biopsy histologic characteristics or sexual history.     

Diffuse filiform polyposis with unique histology mimicking familial adenomatous polyposis in a patient without inflammatory bowel disease

Filiform polyposis is an uncommon entity that is most often encountered in the colon of patients with a history of inflammatory bowel disease (IBD). Filiform polyposis is characterized by a large number of "wormlike" polyps lined by histologically normal colonic mucosa. These polyps can mimic adenomatous polyps. Only rare cases without a history or evidence of IBD have been reported. Neuromuscular and vascular hamartoma of the small bowel is a rare, focal disorder characterized by disorganized smooth muscle fascicles throughout the submucosa accompanied by fibrosis, nerve fibers, ganglion cells, and vessels. To our knowledge, there is only one report of this lesion in the large bowel (cecum), where it presented as a mass. Here we report the case of a 50-year-old man with no known history or symptoms of IBD presenting with filiform polyposis involving the entire colon, clinically mimicking familial adenomatous polyposis, and showing histologic features similar to neuromuscular and vascular hamartoma of the small bowel.     

Primary T-cell lymphoma of the central nervous system

We describe a 64-year-old man who presented with a 9-month history of a progressive neurologic disturbance affecting principally his short-term memory, eye movements, and sense of balance. Computed tomography and magnetic resonance imaging showed a 3-cm mass in the left cerebellar hemisphere. This was removed at craniotomy and proved histologically to be a diffuse non-Hodgkin's lymphoma. Further investigation showed no evidence of lymphoma elsewhere in the body. Immunohistochemical studies with an extensive panel of monoclonal antibodies showed the tumor cells to be T cells staining with the markers UCHL1, MT1, OKT3, and OKT11. Cells of the helper phenotype predominated. A small admixed reactive population of polyclonal B cells and macrophages was also present. The proliferation count as judged with the antibody Ki67 was about 15%. Primary cerebral lymphoma is in itself a rare entity with most cases being of B-cell origin. Primary cerebral T-cell lymphoma is extremely rare and the few previously reported cases are reviewed.     

Extensive colonization of the porcine colonic epithelium by a spirochete similar to Treponema innocens.

Specimens of colonic mucosa from two pigs with diarrhea were examined by light and electron microscopy. The epithelial surfaces of both pigs were extensively colonized by large spirochetes morphologically compatible with Treponema hyodysenteriae or Treponema innocens. The microorganisms were intimately attached end-on to the luminal cells. A weakly beta-hemolytic spirochete similar to T. innocens was isolated from the colon of one of the pigs.     

Syphilitic lymphadenitis diagnosed via fine needle aspiration biopsy

Syphilis is coming back in the recent a few decades especially in the gay and HIV populations. Since syphilis can be "the great mimic" clinically and pathologically, a case report with updated review can be helpful to the medical community. We report, a case of syphilitic lymphadenitis diagnosed via fine needle aspiration biopsy (FNAB). The pitfalls associated with the diagnosis of syphilitic lymphadenitis will be discussed. The patient's medical records were reviewed. The pertinent history, clinical course, and ancillary studies including FNAB cytology with special stains are presented. In addition to the case report, we discuss the diagnosis of syphilitic lymphadenitis and the role of FNAB cytology. This was a 37-year-old man presenting with a two-month history of a growing neck mass, night sweats, and a ten pound weight loss. The patient had been treated one month earlier for primary syphilis. Examination of the head and neck revealed a 3 cm right level II mass. FNAB cytology showed heterogeneous population of lymphocytes and plasma cells suggesting reactive changes. Modified silver staining of the cell block slide was performed and revealed spirochetes, consistent with syphilis. The patient's lymphadenitis resolved with a course of antibiotic treatment. Although lymphadenopathy is a rare presentation of syphilis, it should be included in the differential diagnosis for patients who offer a suspect history. FNAB with silver staining is an effective, minimally invasive way to confirm the diagnosis.     

Cryptococcal infection of the colon in a patient without concurrent human immunodeficiency infection: a case report and literature review

Cryptococcosis is a fungal infection that is rarely reported in patients without human immunodeficiency virus (HIV) infection, especially when the central nervous system (CNS) or pulmonary system is not involved. We report a case of isolated colonic cryptococcosis without disseminated disease in a 64-year-old immunocompetent woman without HIV infection who presented with chronic diarrhea and no episodes of fever or weight loss. The diagnosis was based on histopathology examination. Furthermore, we performed a literature review showing that few reports have been published so far and in the case of colonic cryptococcal infection, the prognosis is favorable among HIV-uninfected patients.

     

Postzygotic D/D translocation homozygosity associated with recurrent abortions

A Robertsonian translocation involving homologous D chromosomes was found in two cases with a history of recurrent abortions. In the first case the propositus was a 37-year-old phenotypically normal man who had a balanced t(14q14q) translocation. In the second case, a 27-year-old phenotypically normal woman was found to be a balanced t(15q15q) translocation carrier. The recurrent abortions in both cases were probably owing to this translocation.     

恶性孤立性纤维性肿瘤2例临床病理分析

目的:探讨恶性孤立性纤维性肿瘤(malignant solitary fibrous tumor,MSFT)的临床病理特征、诊断、鉴别诊断、分子遗传学、治疗及预后.方法:对2例MSFT进行光镜、免疫组织化学研究,并复习相关文献.结果:男性2例,年龄分别为66岁及48岁.发生部位:骶前1例,临床表现为进行性二便障碍3年;后上纵隔1例,临床表现为活动后心慌半个月.肿瘤大小分别为10cm×9 cm×6 cm及12 cm×10 cm×9 cm.镜检:细胞稀少区和细胞丰富区交替分布,两者之间有粗的玻璃样变胶原纤维分隔.密集区肿瘤细胞丰富,呈束状、漩涡状排列,可见血管外皮瘤样结构;瘤细胞呈梭形、短梭形,核染色质粗,异型性明显,有肿瘤性坏死、较多量核分裂( ＞4/10 HPF),局部出血.免疫表型:肿瘤细胞CD34,Bcl-2,CD99及Vimentin弥漫阳性;P53部分阳性,上皮细胞膜抗原局灶阳性;ki-67增殖指数20％ ～ 30％;S100,Desmin,CK及胶质纤维酸性蛋白阴性.结论:MSFT是一种少见的间叶肿瘤,确诊主要依靠形态学及免疫组织化学,需与血管外皮细胞瘤、恶性纤维组织细胞瘤、纤维肉瘤、滑膜肉瘤、恶性间皮瘤、恶性外周神经鞘膜瘤和脑膜瘤等相鉴别.MSFT的预后不良,易复发和转移,根治性切除是主要治疗手段,术后应长期随访.