Metastatic adult granulosa cell tumor mimicking a benign pancreatic cyst.

We report an unusual case of metastatic adult granulosa cell tumor in the head of pancreas mimicking a benign pancreatic cyst in a 43-year-old female. Clinically, it was considered a benign cyst of the pancreas based on its appearance by imaging and that repeated fine-needle aspiration and cytologic examination of cystic fluid failed to identify malignant cells. The cyst in her pancreas grew slowly during the 15 months of close follow-up. Subsequent drainage and open biopsy of the cyst wall established the diagnosis of metastatic adult granulosa cell tumor that was confirmed in pancreaticoduodenectomy specimen. Immunohistochemical study and clinical history were critical to make the correct diagnosis and to differentiate this tumor from other more commonly encountered cystic neoplasms of the pancreas.

Solitary synovial osteochondroma.

Solitary synovial osteochondroma (SSO) is a rare variant of extraskeletal osteochondroma. The aim of this study was to review 5 cases of SSO, including clinical, radiographic, and histopathologic features. Five cases of SSO were retrieved from our files. Histopathologic and radiographic findings were reviewed, and a clinicopathologic correlation was performed. Patients' ages ranged from 33 to 63 years. Knee mass was the most common presentation. All cases were well circumscribed and had multiple cartilaginous lobules surrounded by fibroadipose tissue. Microscopically, lobulated adult-type hyaline cartilage with central calcification was noted. Cytologic atypia was present in one case, but malignant features were absent. Two cases were suggestive of chondrosarcoma on imaging studies. Patients underwent surgery, which was curative in cases for which follow-up was available. In conclusion, SSO is a rare lesion that may mimic low-grade chondrosarcoma at times. Correct recognition of SSO depends on radiographic and clinicopathologic analysis.

Strongyloides colitis is a lethal mimic of ulcerative colitis: the key morphologic differential diagnosis.

Strongyloides stercoralis colitis is a severe, but easily curable, form of strongyloidiasis that carries a high mortality rate if untreated. Autoinfection characteristic of Strongyloides stercoralis frequently makes the infection a life-long disease unless it is effectively treated. Our experience with 4 cases of Strongyloides colitis prompted us to assess the clinical outcome of the disease by literature review. In this case series, the misdiagnosis and resultant mortality rates of Strongyloides colitis are 52% and 39.1%, respectively. A low index of suspicion and morphologic resemblance to ulcerative colitis were the main sources of diagnostic error. Ulcerative colitis alone accounted for 38.5% of the erroneous diagnoses. Features of Strongyloides colitis that contrast with those of ulcerative colitis include (1) skip pattern of the inflammation, (2) distal attenuation of the disease, (3) eosinophil-rich infiltrates, (4) relative intact crypt architecture, and (5) frequent involvement of submucosa. We also found that history of steroid therapy, chronic colitis refractory to conventional immune-modifying management, and endoscopic finding of distal attenuation of the colitis are helpful clues. It is also our experience that if Strongyloides colitis is included in the differential diagnosis, the correct diagnosis can usually be made. Current therapy with ivermectin or albendazole is very effective at a cure rate greater than 98%. We believe that the misdiagnosis and mortality rates of this curable, but often, unnecessarily deadly, infectious disease are alarming and warrant efforts to increase the awareness of the disease.

Cryptococcosis associated with crescentic glomerulonephritis.

Crescentic glomerulonephritis (CGN) is an uncommon form of renal injury in childhood. Whereas many infectious processes are known to be linked to CGN, fungal infections typically are not. This report describes an 11-year-old girl who presented with CGN, cutaneous anergy, and cryptococcal mediastinitis. Whereas cryptococcal disease in children is usually associated with immunodeficiency (inherited or acquired), extensive immunologic evaluation of the patient was notable only for relative CD4 lymphopenia with normal CD4/CD8 ratios. Testing for human immunodeficiency virus was negative. Clinical and diagnostic studies are presented, along with a review of the literature regarding glomerular disease and cryptococcal infections.