Pseudomembranous colitis without diarrhea presenting clinically as acute intestinal pseudo-obstruction.

Pseudomembranous colitis usually presents with diarrhea in a clinical setting of recent antibiotic use. It is uncommon to see it as a cause of obstipation and colonic pseudo-obstruction. We report an unusual case of an elderly woman with hypertension, congestive heart failure, chronic obstructive pulmonary disease, chronic renal insufficiency, and diabetes mellitus, who was admitted with fever, abdominal pain, and distension without diarrhea. She presented with decreased stool frequency and obstipation. She did not respond to conservative management. Colonoscopy revealed a picture of pseudomembranous colitis, and Clostridium difficile toxin was positive. She responded well to metronidazole therapy.

House dust mite, cat, and cockroach allergen concentrations in daycare centers in Tampa, Florida.

BACKGROUND: Allergen exposure in early childhood is a risk factor for sensitization and the development of asthma. Studies performed in Europe, New Zealand, and Singapore indicated the presence of indoor allergens in childcare centers and schools. However, the importance of indoor allergens in daycare centers in humid and warm regions of the world is not known. OBJECTIVE: To measure total mite counts, Der p 1, Der f 1, Fel d 1, and Per a 1 allergens in dust samples and mite allergen airborne concentrations in daycare centers in Tampa, Florida, United States. METHODS: Twenty daycare centers were surveyed for mite, cat, and cockroach allergens in Tampa, FL. One dust and two air samples (one during the day and one during the night) were collected in each center. Dust samples were extracted and analyzed for mite (Der p 1 and Der f 1), cat (Fel d 1), and cockroach (Per a 1) allergens. Mite airborne allergen concentrations were analyzed by RAST inhibition and expressed in standardized mite allergen units per m3 of air (AU/m3). RESULTS: Mites were identified in 15 samples, and concentrations ranged from 10 to 1,200 mites/g (298 +/- 355.2). The most prevalent mite species was Dermatophagoides pteronyssinus ( Der p 1). Der p 1 and/or Der f 1 were detected in 10 daycare centers. Der p 1 was detected in eight centers and ranged from I to 21.8 microg/g of dust (5.4 +/- 6.9); Der f 1 was detected in 3 centers and ranged from 0.2 to 2.1 microg/g of dust (1.3 +/- 0.9). Per a 1 and Fel d 1 were detected in all centers in small quantities; Per a 1 ranged from 8 to 1,806 ng/g (263.1 +/- 449.7) and Fel d 1 from 0.2 to 120 U/g of dust (16.6 +/- 31.7), respectively. Airborne mite allergen was detected in 18 centers and ranged from 0.01 to 2.7 AU/m3 during the day (0.2 +/- 0.6) and from 0.01 to 0.12 AU/m3 during the night (0.06 +/- 0.03), P = 0.001. CONCLUSIONS: Mite, cat, and cockroach allergens are present in daycare centers in Tampa, FL. Mite allergen concentrations exceeded levels that have been associated with sensitization and symptoms in allergic subjects in 40% of these centers.

Molecular staging for melanoma and breast cancer.

Despite increased sensitivity of PCR techniques, routine H&E histology and, in some cases, immunohistochemistry remain the gold standards for the detection of micrometastatic disease. Highly sensitive and specific molecular assays such as RT-PCR provide an ideal way to detect micrometastatic disease in tissues or blood at risk for metastases. RT-PCR has been shown to increase detection of micrometastases, especially in patients with breast cancer and melanoma. These assays have the potential to provide valuable tumor staging and progression information and thus determine the need for further surgery, adjuvant chemotherapy, and antigen-specific immunotherapy. As investigators gain more experience using molecular assays, the results of these assays will be more likely to guide clinical staging and decision making.

Activating SRC mutation in a subset of advanced human colon cancers.

The discovery of Rous sarcoma virus (RSV) led to the identification of cellular Src (c-Src), a non-receptor tyrosine kinase, which has since been implicated in the development of numerous human cancers. c-Src has been found to be highly activated in colon cancers, particularly in those metastatic to the liver. Studies of the mechanism of c-Src regulation have suggested that c-Src kinase activity is downregulated by phosphorylation of a critical carboxy-terminal tyrosine (Tyr 530 in human c-Src, equivalent to Tyr 527 in chicken Src) and have implied the existence of activating mutations in this C-terminal regulatory region. We report here the identification of a truncating mutation in SRC at codon 531 in 12% of cases of advanced human colon cancer tested and demonstrate that the mutation is activating, transforming, tumorigenic and promotes metastasis. These results provide, for the first time, genetic evidence that activating SRC mutations may have a role in the malignant progression of human colon cancer.

Extraesophageal varices.

Esophageal varices are the most common site of variceal bleeding. However, bleeding from varices that are not located in the esophagus may account for up to 30% of all variceal bleeding. Significant varices can occur in the stomach, duodenum, jejunum, ileum, colon, rectum, and biliary tree. They can also occur at the site of a surgical ostomy. These types of varices bleed less commonly than esophageal varices, but they can also be far more difficult to diagnose and treat. The absence of stigmata of recent esophageal variceal bleeding and certain clues in the patient's history and clinical presentation should raise the clinician's suspicion of an extraesophageal site of variceal bleeding. Particularly, patients with extrahepatic causes of portal hypertension, cirrhotic patients with a prior history of gastrointestinal surgery, and patients who present with profound bleeding but without hematemesis need to be evaluated further if an obvious site of esophageal variceal bleeding is not seen on initial endoscopy. In this article, we review the features particular to extraesophageal varices as well as the diagnosis and management of bleeding from these varices. We use the term extraesophageal rather than ectopic because the term ectopic varices implies exclusion of both esophageal and gastric varices.

Gastric outlet obstruction caused by microperforation of Helicobacter pylori-related antral ulcer.

We report a Helicobacter pylori-related antral gastric ulcer that continued to cause symptoms despite H. pylori eradication. The patient had progressive gastric outlet obstruction, raising the possibility of a malignancy. On exploratory laparotomy, he was found to have a large inflammatory mass surrounding a contained microperforation.

Serial determinations of Der p 1 and Der f 1 show predominance of one Dermatophagoides species.

One dust sample each month was collected for an average of 11 months throughout the year from the bedroom carpet of 39 mite allergic, asthmatic individuals living in the Tampa Bay area of Florida. Dust samples were collected from a square meter area from the bedroom carpet for 2 min using a portable vacuum cleaner and analyzed using two-site monoclonal antibody assays. The geometric mean of Dermatophagoides allergens Der p 1 and Der f 1 levels measured in each individual home was used in the statistical analysis of the results and reflects the average allergen level per year per home. Der p 1 levels were greater than Der f 1 in 21 homes; five homes had between 1.1 and 5 times more; one home had between 5 and 10; and 15 had between 10 and 175. Der f 1 levels were greater than Der p 1 in 18 homes; seven homes had between 1.1 and 5 times more; four had between 5 and 10; and seven homes had between 10 and 44. Spearman rank analysis of the results yielded a negative correlation coefficient (Rho) = -0.213 (p = 0.19) between Der p 1 and Der f 1 levels. These data suggest that when mite allergen levels reach a geometric mean value of approximately 2 micrograms/gram of dust throughout a year, one mite species predominates over the other.

Spetial and temporal distribution of house dust mite (Astigmata:Pyroglyphidae) allergens Der p 1 and Der f 1 in Barbadian homes.

House features contribute to house dust mite abundance and, therefore, exposure to mite allergens. Our study assessed the hypothesis that modernization of the domestic environment in a tropical setting may lead to a level of allergen from the house dust mites Dermatophagoides pteronyssinus (Trouessart) and D. farinae Hughes that previously has been defined clinically as at risk for people who suffer from allergic disease. Allergen (Der p 1 and Der f 1) levels were measured at 4 sites (mattress, bedroom floor, living room floor, and furniture) in 17 houses in Barbados during dry and rainy seasons. Der p 1(17 of 17 homes) at all 4 sites did not vary significantly from the dry to rainy season. Allergen levels varied according to site, and were highest in living room furniture in both seasons (geometric mean 40.37 and 64.17 micrograms/g, respectively). Concentration of Der p 1 allergens were higher in concrete than in wood or mixed concrete and wood houses. Der f 1(9 of 17 homes) levels were lower than Der p 1 by 1/1,000 (both seasons). Results indicate that season is less important in regard to levels of Der p 1 than house construction and confirm other studies that implicate D. pteronyssinus as a more abundant source of allergen than D. farinae in this tropical setting.

Spetial and temporal distribution of house dust mite (Astigmata: Pyroglyphidae) allergens Der p 1 and Der f 1 in Barbadian homes

Houses features contribute to house dust mite abundance and, therefore, exposure to mite allergens. Our study assessed the hypothesis that modernization of the domestic environment in a tropical setting may lead to a level of allergen from the house dust mites Dermatophagoides pteronyssinus (Trouessart) and D. farinae Hughes that previously has been defined clinically as at risk for people who suffer from allergic disease. Allergen (Der p 1 and Der f 1) levels were measured at 4 sites (mattress, bedroom floor, living room floor, and furniture) in 17 houses in Barbados during dry and rainy seasons. Der p 1 (17 of 17 homes) at all 4 sites did not vary significantly from the dry to rainy season. Allergen levels varied according to site, and were highest in living room furniture in both seasons (geometric mena 40.37 and 64.17 micrograms/g, respectively). Concentration of Der p 1 allergens were higher in concrete than in wood or mixed concrete and wood houses. Der f 1 (9 of 17 homes) levels were lower than Der p 1 by 1/1,000 (both seasons). Results indicated that season is less important in regard to levels of Der p 1 than house construction and confirm other studies that implicate D. pteronyssinus as a more abundant source of allergen than D. farinae in this tropical setting.(AU)

Association of cocaine and methamphetamine use with giant gastroduodenal ulcers.

OBJECTIVES: Giant gastric and duodenal ulcers (>2-3 cm in greatest dimension) are reported to have higher rates of complication and mortality and to be associated with increasing age, renal failure, and use of nonsteroidal antiinflammatory drugs (NSAIDs). This study investigated the outcome and associations of gastric and duodenal ulcers >2.5 cm compared to ulcers of lesser size. METHODS: Records from all patients with gastric and duodenal ulcers >0.5 cm diagnosed by upper endoscopy between January 1994 and September 1995 were studied for evidence of concurrent use of aspirin, NSAIDs, methamphetamine, and cocaine, as well as for transfusion requirements, length of hospital stay, mortality, surgery, rebleeding, Helicobacter pylori infection, and malignancy. RESULTS: A logistic regression analysis of the 220 patients identified revealed that recent methamphetamine and/or cocaine use was significantly predictive of giant ulcer formation (p = 0.0002) with an odds ratio of 9.66. Also significant was younger age (p = 0.026) and aspirin or NSAID use (p = 0.046). H. pylori infection was significant only for giant gastric ulcers (p = 0.031). Ulcer size did not predict mortality, rate of rebleeding, requirement for surgery, transfusion requirements, or length of hospital stay. However, giant gastric ulcers were significantly more likely to be malignant (p = 0.002). CONCLUSIONS: Giant gastric and duodenal ulcers were strongly associated with stimulant abuse. They were also associated with younger age and use of aspirin or NSAIDs. Additionally, giant gastric ulcers were associated with malignancy and H. pylori infection. Ulcer size did not predict rate of complications or outcome.

High-sensitivity detection of minimal residual breast carcinoma using the polymerase chain reaction and primers for cytokeratin 19.

We have developed a reverse transcriptase-polymerase chain reaction (RT-PCR) assay to identify breast carcinoma cells in bone marrow aspirates with high sensitivity and specificity. This assay relies on the detection of cytokeratin 19 (K19) RNA by nested primer PCR followed by annealing to a (32P)-labeled internal sequence probe and autoradiography. In reconstitution experiments, this assay is capable of detecting 10 fg of admixed mammary tumor RNA in 1 microgram of normal marrow RNA (a dilution of 1:10(7)). Thirty of 30 primary breast tumor specimens, 19 of 19 cytologically positive bone marrow aspirate specimens, and three of 11 aspirate negative/biopsy positive specimens showed detectable K19 transcript. This assay shows high specificity, with 50 of 52 negative control aspirates showing no detectable amplification product. False-positive amplification was noted in two of 18 aspirates obtained from patients with active chronic myelogenous leukemia. Of stage II and III postsurgical breast carcinoma patients with histologically negative bone marrows and no radiographic bone disease, 14 of 30 were K19 positive by PCR. RT-PCR analysis of K19 transcript is a highly sensitive and specific method of detecting and monitoring low-level metastatic disease in patients with primary carcinoma of the breast. The presence of K19 RNA in histologically negative bone marrows suggests that this assay may prove a powerful monitor for patients undergoing curative therapy as well as a novel prognostic indicator.

Mite sensitivity and exposure in the city of Santa Fe, Argentina.

Little information is available on mite allergen levels and rates of sensitization to domestic mites in South America. The purpose of this study was to establish the rate of sensitization to domestic mites in asthmatics and measure mite allergen levels in pillows and mattresses of mite allergic individuals in Santa Fe, Argentina. Dust samples were collected from the pillows and mattresses of 56 asthmatics (24 females and 32 males, mean age 17.6 +/- 11.5 years), who had been previously skin tested with standardized extracts of Dermatophagoides pteronyssinus, Dermatophagoides farinae and (1:50 w/v) extracts of Aleuroglyphus ovatus, Blomia tropicalis, Chortoglyphus arcuatus. A wheal > or = 3 mm was considered positive. Sensitization to Lepidoglyphus destructor and Euroglyphus maynei was determined by RAST and considered positive when a serum bound > or = 1% of the total counts added. Forty six individuals had a positive skin test to D. pteronyssinus, 43 to D. farinae, 27 to A. ovatus, 38 to B. tropicalis, 27 to C. arcuatus; 38 of 54 individuals had a positive RAST to E. maynei and 22 of 54 to L. destructor. The mean Group 1 (Der p 1 + Derf 1) level in pillows (n = 48) was 6.7 micrograms/g (1-55.4) and in mattresses (n = 52) 4.3 micrograms/g (1-38.8). There is a high degree of sensitization to domestic mites among asthmatics in Santa Fe. High mite allergen levels (> 2 micrograms/g) can be detected very often in pillows and mattresses.

Clinical significance of bone marrow metastases as detected using the polymerase chain reaction in patients with breast cancer undergoing high-dose chemotherapy and autologous bone marrow transplantation.

PURPOSE: The present study evaluates the clinical significance of detection of cytokeratin 19 (K19) in the bone marrow of patients with breast cancer undergoing high-dose chemotherapy (HDCT) and autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS: We studied retrospectively cryopreserved bone marrow aspirates from 83 patients with high-risk stage II, III, and IV breast cancer obtained before bone marrow harvest but after induction chemotherapy. All samples were histologically negative for metastases. Polymerase chain reaction (PCR) for K19 was performed according to methods described previously and results were correlated with the probability of relapse following HDCT and ABMT. RESULTS: The incidence of occult metastases as defined by PCR for K19 message was 52% for 19 stage II, 57% for 14 stage III, and 82% for 50 stage IV patients (two-tailed P = .0075, chi 2 test). The probability of relapse at 3 years after ABMT was 32% and 94% for K19-positive stage II/III and stage IV patients, respectively, versus 10% and 14% for K19-negative stage II/III and stage IV patients, respectively. The difference was significant for stage IV patients (two-tailed P = .0002). CONCLUSION: It has been shown that PCR is a highly sensitive method to detect K19 message in the bone marrow. The incidence of K19 positivity in bone marrow increases significantly with advancing stage. In patients with breast cancer, especially metastatic breast cancer, undergoing HDCT and ABMT, the presence of K19 is associated with a poor prognosis.

Positive nasal challenge responses to Blomia tropicalis.

BACKGROUND: Blomia tropicalis, a dust mite commonly found in subtropical and tropical environments, is the fourth most common mite in the United States. Thirty-eight percent of 167 consecutive subjects evaluated for allergic respiratory symptoms in the Tampa Bay area had positive skin test responses to B. tropicalis. METHODS: Nasal challenges were performed in 19 subjects with allergic rhinitis; 12 had positive skin test responses to B. tropicalis (group I), and seven had negative skin test responses to B. tropicalis but positive skin test responses to Dermatophagoides pteronyssinus and D. farinae (group II). Subjects were challenged with a normal saline control solution and increasing concentrations of a 1 mg/ml in-house extract of B. tropicalis (1:125,000 vol/vol, 1:25,000 vol/vol, 1:5000 vol/vol, 1:1000 vol/vol, and 1:200 vol/vol). Inspiratory nasal airway resistance (was measured every 5 minutes for 15 minutes by posterior rhinomanometry at 50 Pa after each nasal challenge. RESULTS: Nasal challenge response was considered positive and stopped when the mean inspiratory nasal airway resistance was greater than twice the mean inspiratory nasal airway resistance after the normal saline challenge. Ten of 12 (83%) subjects in group I and none of seven (0%) subjects in group II had positive nasal challenge responses to B. tropicalis (p = 0.0024). CONCLUSION: B. tropicalis is allergenic and should be considered as a cause of allergic rhinitis when evaluating a patient who lives in an area where it is endemic.