Gene expression signature as an ancillary method in the diagnosis of desmoplastic melanoma.

Desmoplastic melanoma (DM) is a rare fibrosing variant of melanoma that can be difficult to diagnose. One of the diagnostic challenges is its distinction from a melanocytic nevus with desmoplasia. Here we investigate the use of a 23-gene signature, which has previously been shown to distinguish benign from malignant melanocytic neoplasms. We assessed 50 cases with a differential diagnostic consideration of DM that underwent gene expression testing. Hematoxylin and eosin-stained sections were reviewed, and the final cohort included 20 DMs, 5 nondesmoplastic melanomas, and 27 desmoplastic melanocytic nevi. Of the 20 DMs, the gene expression score was positive ("likely malignant") in 15 tumors, indeterminate in 1, and negative ("likely benign") in 4. None of the desmoplastic melanocytic nevi were positive. The gene expression score was negative in 24 of the melanocytic nevi and indeterminate in the remaining 3. Nine DMs were also analyzed cytogenetically by single-nucleotide polymorphism (SNP) array. The SNP array revealed chromosomal copy number aberrations consistent with melanoma in 7 DMs and failed to show any aberrations in 2. The results of SNP array analysis and gene expression testing were discordant in 4 cases. Our results document limitations in the sensitivity of both the gene expression signature and SNP array for the detection of DM. Nonetheless, our findings suggest a potential role of the gene expression signature as ancillary supportive evidence for the distinction of DM from desmoplastic nevus because positive scores were only seen in melanomas.

Primary mucinous carcinoma of the skin: the Mayo Clinic experience over the past 2 decades.

BACKGROUND: Primary mucinous carcinoma of the skin (PMCS) is a rare adnexal eccrine sweat gland neoplasm, often mistaken for metastasis from extracutaneous sites or misdiagnosed. Primary mucinous carcinoma of the skin is a slow-growing tumor with a high recurrence rate after conventional excision. OBJECTIVE: To describe clinicopathologic features, rate of recurrence, and metastasis and to review relevant literature. MATERIALS AND METHODS: The authors identified patients with PMCS treated from January 1992 through December 2012 at Mayo Clinic. The authors retrospectively reviewed medical records and histology slides. Relevant publications were identified through Ovid MEDLINE and PubMed. RESULTS: Six patients with PMCS were identified (1 male). The average age at diagnosis was 63 years. Tumor size ranged from 0.5 to 2.0 cm, and all were confined within the dermis. No evidence of metastatic mucinous adenocarcinoma was documented at the time of diagnosis. Five patients underwent Mohs micrographic surgery, and 1 was treated with wide local excision. There were no episodes of recurrence or metastases after a median follow-up of 20 months (range, 0.5-207 months). CONCLUSION: Mohs micrographic surgery may offer reduced recurrence rates and better outcomes in PMCS. Further studies with longer follow-up and bigger cohorts of patients with PMCS are warranted.

Iron overload in allogeneic hematopoietic stem cell transplant recipients.

CONTEXT: Patients who undergo hematopoietic stem cell transplant are at an increased risk of developing iron overload. OBJECTIVES: To describe the effect of hepatic iron overload on hematopoietic stem cell transplant recipients and to validate the utility of histologic scoring system of iron granules in the liver. DESIGN: Records of 154 post allogeneic hematopoietic stem cell transplant patients were reviewed. Forty-nine patients underwent liver biopsy. Histologic hepatic iron overload was defined as a score of 2 or greater (scale, 0-4). RESULTS: Twenty-eight of 49 patients (57%) evaluated by liver biopsy had hepatic iron overload; 17 had moderate to severe hepatic iron overload (score, 3 or 4). In multivariate analysis, a significant correlation was discovered between hepatic iron overload and the number of transfusions (P < .001), posttransplant serum ferritin levels (P=.004), lactate dehydrogenase levels (P=.03), and the development of blood stream infections (P= .02). There was no correlation between hepatic iron overload and abnormal liver function test results. While 37 patients (76%) died after receiving a transplant, mortality was not influenced by hepatic iron overload but was significantly higher in older patients, in patients with lower serum albumin levels, higher serum bilirubin levels, and higher clinical grade of acute graft-versus-host disease (P=.04, P=.001, P=<.001, and P .004, respectively). CONCLUSIONS: Hepatic iron overload is commonly identified in hematopoietic stem cell transplant patients and can be accurately diagnosed by liver biopsy. In addition, hepatic iron overload has been identified in patients receiving as few as 25 units of packed red blood cells, with elevated posttransplant serum ferritin levels, and with blood stream infections.

Discordant Streptococcus agalactiae (Group B streptococcus) gestational infection in monochorionic/diamniotic and dichorionic/diamniotic twins.

Infection due to Streptococcus agalactiae or Group B streptococcus may be acquired during parturition or gestation. Discordant twin gestational Group B streptococcus infections are rarely reported. We describe two cases of fatal discordant gestational Group B streptococcus infection in both a monochorionic/diamniotic pregnancy and in a dichorionic/diamniotic pregnancy. In both instances, cultures, examination of the placentae, and autopsy findings demonstrated infection by Group B streptococcus in only the presenting fetus. Despite the ubiquity of this organism, this is the first documented case of discordant gestational Group B streptococcus infection in monochorionic/diamniotic twins and only the third case documented in dichorionic/diamniotic twins.

Naproxen-induced liver injury.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been reported to induce liver injury. Patterns of the injury usually range from mild elevations of liver enzymes to sometimes severe fulminant hepatic failure. Likewise, naproxen is a propionic acid derivative NSAID that was introduced in 1980 and has been available as an over-the-counter medication since 1994, but has rarely been reported to cause liver injury. METHODS: We treated a 30-year-old woman with jaundice and intractable pruritus that developed shortly after taking naproxen. We reviewed the medical history and liver histopathology of the patient as well as all previously published case reports of naproxen-associated liver toxicity in the English language literature. RESULTS: The liver biochemical profile of the patient revealed a mixed cholestasis and hepatitis pattern. Consecutive liver biopsies demonstrated focal lobular inflammation, hepatocyte drop-out, and a progressive loss of the small interlobular bile ducts (ductopenia). The biopsy performed two years after onset of the disease showed partial recovery of a small number of bile ducts; however, 10 years passed before the biochemical profile returned to near normal. CONCLUSIONS: Naproxen-associated liver toxicity remains a rare entity, but should be considered in any patient presenting with cholestasis shortly after its use. Liver injury is most commonly seen in a mixed pattern characterized by cholestasis and hepatitis. The resulting liver damage may take years to resolve.

Comparison of time to positivity of the VersaTREK® REDOX 80-mL and the REDOX EZ draw 40-mL blood culture bottles for common bacterial bloodstream pathogens.

The VersaTREK(®) microbial detection system offers 2 media formulations, an aerobic and an anaerobic bottle available in a 40-mL direct draw format and an 80-mL format. The 40-mL EZ Draw(®) bottle can be inoculated with a maximum volume of 5 mL, while the REDOX 80-mL bottle accommodates a 10-mL volume. The effect of volume of blood inoculum on time to positivity (TTP) has not been clearly established with these bottle types. This study utilized simulated blood cultures seeded with clinically relevant microorganisms in human blood to evaluate the impact of inoculum volume and organism load on TTP for the 2 bottle types. For 13/15 organisms, the EZ Draw bottle flagged positive earlier than the REDOX 80-mL bottles. The lower volume of blood inoculum did not negatively impact TTP using the EZ Draw blood culture bottles as compared to REDOX 80-mL bottles.

Misidentification of Pandoraea sputorum isolated from sputum of a patient with cystic fibrosis and review of Pandoraea species infections in transplant patients.

Pandoraea species are considered emerging pathogens in cystic fibrosis (CF) patients, but few data exist regarding outcomes of patients colonized with these organisms. We report a case of Pandoraea sputorum colonization in a CF patient under consideration for lung transplantation and review five cases of lung transplantation involving Pandoraea species.

Desulfovibrio fairfieldensis bacteremia associated with choledocholithiasis and endoscopic retrograde cholangiopancreatography.

Desulfovibrio fairfieldensis is a gram-negative, curved, motile, anaerobic bacillus. D. fairfieldensis has been isolated only from human specimens and is considered a normal resident of the human gastrointestinal tract. We report the second case of Desulfovibrio bacteremia associated with choledocholithiasis and review the other reported cases of D. fairfieldensis bacteremia.

Peritonitis due to Cunninghamella bertholletiae in a patient undergoing continuous ambulatory peritoneal dialysis.

Peritoneal dialysis-associated peritonitis due to fungi of the class Zygomycetes occurs very rarely. A case of fungal continuous ambulatory peritoneal dialysis peritonitis due to Cunninghamella bertholletiae is reported in a 39-year-old Aboriginal woman with end-stage renal failure and diabetes mellitus. This isolate was found to be resistant in vitro to amphotericin B, 5-fluorocytosine, fluconazole, itraconazole, ketoconazole and voriconazole. However, this patient was successfully treated with voriconazole and removal of the Tenckhoff dialysis catheter. Zygomycoses are an emerging threat among immunocompromised patients, including those with chronic renal failure. Zygomycosis due to C. bertholletiae is frequently fatal and is often non-responsive to systemic antifungal therapy. This is believed to be the first reported case of C. bertholletiae causing peritonitis in humans and one of the minority of cases involving this organism with a successful outcome.

Peritonitis due to Curvularia inaequalis in an elderly patient undergoing peritoneal dialysis and a review of six cases of peritonitis associated with other Curvularia spp.

Fungal peritonitis due to Curvularia species in patients undergoing peritoneal dialysis is a very rare problem. We report a case of peritonitis caused by Curvularia inaequalis. This is the first report in the English literature of this species causing human infection. We also review the six previously reported cases of continuous ambulatory peritoneal dialysis peritonitis caused by other Curvularia species.