Improved Diagnostic Sensitivity of Bowel Disease of Prematurity on Contrast-Enhanced Ultrasound

Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates.     

Danazol administration after gonadotrophin-releasing hormone analogue reduces rebound of uterine myomas [published erratum appears in Hum Reprod 1998 Mar;13(3):780]

We report the results of administration of danazol after suspension of gonadotrophin-releasing hormone analogue (GnRHa) therapy for uterine myomas. A total of 21 women with uterine myomas was treated with 100 mg danazol for 6 months after GnRHa therapy. Uterine volume and endocrine status were monitored monthly by ultrasound and assay of plasma gonadotrophins, oestradiol and progesterone. The results show a rebound of uterine volume about 30% less than in controls at the end of danazol therapy. Menstrual cyclicity returned after 65 +/- 3 days in 16 subjects and five patients remained amenorrhoeic. Hormone assays confirmed renewed ovarian function in the women whose menstrual periods returned. Bone mineral content was substantially reduced during GnRHa treatment but improved significantly during danazol therapy even in the women who remained amenorrhoeic. These results show the utility of danazol in prolonging the therapeutic effects of GnRHa. The mechanism by which danazol inhibits rebound of uterine volume may be due to its antiprogesterone effects on uterine myomas.      

Evidence for arsenic as the immunosuppressive component of gallium arsenide.

Gallium arsenide (GaAs) has been shown previously to suppress the in vivo antibody-forming cell (AFC) response to sheep erythrocytes (SRBC) when administered intratracheally at concentrations between 50 and 200 mg/kg. In the present studies, direct addition of GaAs to in vitro-generated antibody cultures resulted in dose-dependent suppression of the primary antibody response, and was only seen when GaAs was added within 36 hr following immunization. Using atomic absorption spectrophotometry on tissue samples from mice exposed to 200 mg/kg GaAs, arsenic concentrations were found to peak in the spleen at 24 hr and decline, whereas gallium concentrations continue to rise through 14 days. Concentrations of each metal in the spleen at 24 hr are comparable to the concentrations achieved for each metal when GaAs is added at 25 microM to the in vitro model system. The 24 hr time point was chosen for comparison because all in vivo-in vitro studies were conducted using spleens from mice 24 hr after GaAs exposure. NaAsO2 and Ga(NO3)3 suppressed the AFC response dose-dependently, and in a time-dependent manner similar to GaAs when added to the in vitro system. However, based on IC50 values for each salt, the role of the gallium component in the immunosuppression appears weak. Oxalic acid (OA) and meso-2,3-dimercaptosuccinic acid (DMSA), chelators of gallium and arsenic respectively, were added to cultures with GaAs to confirm that arsenic was the primary immunosuppressive component. DMSA dose-dependently blocked GaAs-induced immunosuppression in vitro, while OA had no effect. The metal-binding compounds were determined to be specific for the metals used in these studies and did not cross-react with one another. DMSA was evaluated for its ability to prevent suppression of the AFC response in splenocytes from GaAs-exposed mice and was able to block GaAs-induced suppression of the AFC response when given sc every 4 hr beginning 1 hr prior to GaAs exposure. These data indicate that the arsenic component of GaAs is the major contributor to the GaAs-induced immunosuppression and that this effect occurs within the first 36 hr of the 5-day culture period in a concentration-dependent manner.     

Endoscopic retrograde cholangiopancreatography in the preoperative diagnosis of pancreatic neoplasms associated with cysts

Neither computed tomography (CT) nor ultrasonography reliably distinguishes neoplastic from non-neoplastic pancreatic cysts. More invasive tests such as angiography or biopsy fail to differentiate these lesions in up to a third of patients. Because appropriate treatment differs greatly for these two classes of lesions, the clinician requires a more accurate means of confirming or excluding neoplasia. In an effort to refine the preoperative diagnosis of pancreatic cysts and evaluate the utility of endoscopic retrograde pancreatography (ERCP), we evaluated 11 patients with proven pancreatic neoplasia associated with cysts who underwent preoperative ERCP and CT scanning. Four patients had microcystic cystadenomas, two had a mucinous cystadenoma, one had a mucinous cystadenocarcinoma, and four had adenocarcinomas associated with cysts. CT identified a pancreatic cystic lesion in each patient. In all patients, ERCP showed either focal irregular narrowing, occlusion, or displacement of the main pancreatic duct at the corresponding location without the ductal changes of chronic pancreatitis. This helped to preoperatively differentiate these lesions from pseudocysts, hastening appropriate operation, obviating further testing and consultation, and aiding the intraoperative surgical strategy.     

Time-dependent changes in bone, placental, intestinal, and hepatic alkaline phosphatase activities in serum during human pregnancy

To measure changes in bone alkaline phosphatase (EC 3.1.3.1) activity in serum as a function of duration of pregnancy, we adapted our existing alkaline phosphatase (ALP) isoenzyme assay (which has been used to measure bone, hepatic, and intestinal ALP activities in serum, in the absence of placental ALP) to allow quantification of individual ALP isoenzyme activities in the presence of placental ALP. The resulting CV for repeat measurements of bone ALP activity in artificial isoenzyme mixtures ranged from 23% for samples in which the bone isoenzyme represented 7% of total ALP activity to 11% for samples in which bone ALP accounted for 48% of total ALP activity. Values for repeat determinations of bone ALP activity in human serum samples (i.e., including samples obtained from pregnant women and from nonpregnant controls) varied by an average of 18%. We find, in initial applications of this method, that (a) the amount of bone ALP activity in serum is increased during pregnancy (P less than .001), and remains increased at six weeks postpartum, in non-lactating women (P less than .001), and (b) bone ALP activity at term was not significantly different in pregnant women with pre-eclampsia, diabetes, premature rupture of membranes, or premature labor, compared with normal pregnancies at term. Our data support the hypothesis that maternal bone formation may be increased during pregnancy.     

Pneumothorax and other lung diseases: effect of altered resolution and edge enhancement on diagnosis with digitized radiographs

Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).     

Characterization of antibody and selection of alternative drug therapy in hydrochlorothiazide-induced immune hemolytic anemia

The authors report the clinical and laboratory findings of a patient who had severe immune hemolytic anemia due to hydrochlorothiazide (HCTZ). In this case, the HCTZ antibody reacted not only with other thiazide and thiazide-like drugs, but also with a chemically unrelated diuretic, ethacrynic acid. These results indicate that HCTZ antibody activity is not restricted solely to the thiazides and imply that therapy with any of the reactive drugs would be contraindicated for this patient. The serologic screening for drug reactivity may be useful for selecting alternative therapy for patients with drug-induced immune hemolytic anemia.