Effect of prior antibiotic treatment on middle ear disease in children

The effect of prior antibiotic treatment on the course of otitis media was assessed in a group of 62 children who experienced 83 episodes of ear infection during 3 years of observation. Bacterial quantitation in middle ear fluids demonstrated a significantly higher colony count in symptomatic children (3.9 x 10(4) +/- 12 bacteria per milliliter) compared to asymptomatic children (6.3 x 10(3) +/- 10 bacteria per milliliter; p = .05). Bacterial counts similarly tended to be higher in children with Streptococcus pneumoniae (4.0 x 10(6) +/- 16 bacteria per milliliter) and Hemophilus influenzae (2.0 x 10(6) +/- 16 bacteria per milliliter), who were more often symptomatic (73% and 55%, respectively, versus 38%) than children with Moraxella catarrhalis (7.9 x 10(3) +/- 2). Antibiotic therapy between 3 and 30 days prior to bacterial diagnosis was associated with a reduction in symptoms from 70% to 38% (p less than .025). However, prior treatment did not statistically reduce bacterial colony counts, although S pneumoniae decreased 90% in the previously treated group. Resistance to ampicillin occurred in 0% of S pneumoniae, 39% of nontypeable H influenzae, and 80% of M catarrhalis subjects without prior treatment and in 0%, 46%, and 100%, respectively, of subjects previously treated (p less than .025). These data suggest that prior treatment has a significant impact on the subsequent course of otitis media in children.

Value of dual-energy CT in differentiating focal fatty infiltration of the liver from low-density masses

Focal (irregular, partial) fatty infiltration of the liver may simulate neoplastic or other hypodense masses on CT. On the basis of previous observations of the phenomenon that differences in X-ray attenuation diminish with increasing energy of X-rays used, we performed a preliminary study to determine if dual-energy CT could be used to discriminate between fatty infiltration and hypodense liver masses. Dual-energy CT at 140 and 80 kVp was performed in 14 patients undergoing liver biopsy and in seven control subjects with presumedly normal liver. Attenuation measurements were taken, and the changes in attenuation between 140 and 80 kVp were calculated. The mean changes in attenuation were 3.5 H for normal liver (n = 7), 2.5 H for hypodense liver masses (n = 6), 13 H for fatty liver (n = 5), 0.3 H for fatty liver combined with hemochromatosis or hemosiderosis (n = 3), and 2 H for the spleen (n = 18). The change in attenuation increased as the fat content in the liver increased. Analysis of variance showed a statistically significant difference (p less than .001) between fatty liver and the other groups. A difference greater than 10 H was unique to fatty infiltration. These results suggest that dual-energy CT may help to differentiate focal fatty infiltration of the liver from low-density neoplastic or other lesions, but only if the iron content of the liver is not increased.

Arachidonic acid metabolites in middle ear effusions of children

Middle ear effusions (MEEs) from 78 children (98 ears) with otitis media were examined for products of arachidonic acid (AA) metabolism, including leukotrienes B4, C4, D4, and E4 and prostaglandins D2 and E2, by high-performance liquid chromatography. Leukotrienes B4 and D4 were recovered most frequently: 59% and 54%, respectively. Leukotriene B4 was found in highest concentration, 1.29 +/- 3.46 ng/0.1 mL. The concentrations of leukotrienes B4 (p less than .03), (4 (p less than .01), and E4 (p less than .02) were significantly higher in culture-positive than in culture-negative MEEs. Neither the concentration nor the type of AA metabolite correlated with bacterial species isolated, chronicity of effusion, age of subject, or consistency of MEE. These data suggest that the AA metabolites are synthesized relatively frequently during otitis media of childhood. Leukotriene B4 is the most frequently detected AA metabolite in MEEs and is highly associated with the presence of viable bacteria.

Lecithin cholesterol acyltransferase deficiency: ultrastructural examination of sequential renal biopsies

We present the renal biopsy findings in two brothers with nephrotic syndrome and lecithin:cholesterol acyltransferase deficiency. Mesangial expansion and capillary wall thickening were accompanied by numerous extracellular osmiophilic membranes within round lucent spaces, by round lamellar deposits, and by amorphous deposits containing thread-like structures with cross-striations. A second biopsy in one of the brothers, when he had developed renal insufficiency 8 yr later, showed increased mesangial and capillary wall thickening. The deposits, which had been in predominantly subepithelial and intramembranous locations, were now in a more prominent subendothelial location. The subepithelial localization of the deposits seen on initial examination may be related to their cationic charge, perhaps with binding to glomerular polyanion, and to uptake by glomerular epithelial cells. The accumulation of lipid is associated with progressive mesangial and glomerular sclerosis.

Renal involvement in tuberous sclerosis

TSC in the kidney is expressed principally as renal cysts and angiomyolipomas. Both abnormalities may occur separately or together, and both are commonly multiple and bilateral. Cystic disease is sometimes so severe as to be confused with polycystic kidney disease, although the histopathologic findings are practically diagnostic of TSC. Severe cystic disease causes renal insufficiency; large angiomyolipomas predispose to life-threatening hemorrhage. Renal malignancies have been reported in what appears to be a significant number of patients. We hypothesize that the renal abnormalities result from cell hyperplasia and hypertrophy, much like the other abnormalities of tuberous sclerosis, such as cerebral tubers and cardiac rhabdomyomas. The renal abnormalities can therefore be regarded as an expression of the TSC gene, and their recognition as such carries importance for treatment and counseling.

Mesangiolysis: an important glomerular lesion in thrombotic microangiopathy

Six cases of malignancy-associated thrombotic microangiopathy and eight cases of idiopathic microangiopathy have been studied by renal biopsy. All patients of both groups had mild to severe renal impairment and microangiopathic hemolytic anemia. The renal lesions were histopathologically identical in the two groups. The most characteristic abnormalities were glomerular mesangiolysis and glomerular and arteriolar thrombosis. Subendothelial widening, presumably due to entrapment of blood components, and the formation of capillary and arteriolar thrombi may be attributed to endothelial damage. Glomerular fibrinogen was demonstrated by immunofluorescence in a majority of cases. Immunofluorescence also showed glomerular immunoglobulin M (IgM) and Clq in a majority of cases and C3 in slightly less than half. Mesangiolysis, present in every case, resulted in coalescence of capillary lumina, but mesangiolysis is a bland process, easily overlooked. The mesangial waists of the glomerular tufts seemed to unravel and come apart, with no inflammatory reaction or fibrin deposition on the luminal surface. The presence of capillary enlargement was confirmed morphometrically as an increased proportion of glomerular sectional area. In what appeared to be a late stage of mesangiolysis, the mesangium was thickened by pale fibrillary material, producing a lobulated glomerular tuft and eventual glomerular solidification. The early stages of mesangiolysis may be reflected only in glomerular capillary ectasia, whereas the late stages produce a distinctive form of glomerular sclerosis.

Development of a model quality-of-care assessment program for adult preventive care in rural medical practices

A four-year project of quality-of-care assessment for 37 practices in rural North Carolina used chart abstraction and formal feedback to practitioners to improve compliance standards for 13 adult health maintenance interventions. In 1987, performance of Papanicolaou (Pap) test within two years ranged from 20% to 100% (mean, 61%), mammogram 0% to 70% (mean, 20%), and influenza vaccination 0% to 90% (mean, 59%). Practices received individual results and remediation took place for those practices that performed poorly; a reaudit took place in 1989, with improvement in all measures for all practices, except the influenza vaccination. Compliance results for 1989 were 30% to 100% (mean, 67%) for the Pap test, 10% to 100% (mean, 40%) for the mammography screening, and 5% to 80% for the influenza vaccination. These results suggest that coordinated quality-of-care assessment for rural practices can be performed with a modest administrative burden and substantial benefit to the practices.

Monoclonal antibody to human cartilage cells and its reactivities to chondrocytic tumors

A murine monoclonal antibody (E10) was made against cultured cartilage cells. The E10 antibody binding is localized to the surface of cultured cartilage cells in suspension and is present in the cytoplasm in paraffin embedded sections. There is no reactivity with cartilage matrix, or with the matrix of cartilaginous tumors. Reactivity is removed by treatment with trypsin and hyaluronidase, but not by treatment with heparinase, neuraminidase, and chondroitinase. Regeneration of E10 antigen after trypsinization takes 48 hours in chondrocytes in tissue culture. SDS-polyacrylamide gel electrophoresis of an E10 immune precipitate of cultured chondrocytes results in two peaks: one at a very high molecular weight and a small fragment at approximately 250 kd. Specificity has been demonstrated by cytofluorometry, immunofluorescence, and immunohistochemistry, in both frozen and paraffin-embedded tissues. Positive reactivity was seen in cultured cartilage cells, chondrocytes in fetal and adult cartilage, chondrosarcomas, and chordomas. Minimal reactivity was found in a chondromyxoid liposarcoma. Acinar cells of salivary and sweat glands and mast cells in various tissues and tumors were also positive. There was no reactivity with other tissues and tumors, including myxoid and mucinous tumors and epithelial tissues.

Changes in nasopharyngeal flora during otitis media of childhood

The nasopharyngeal flora of healthy children were compared with flora in children with otitis media caused by nontypable Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis. Forty healthy children were followed prospectively and compared with 70 children with 43 episodes of nontypable H. influenzae, 21 episodes of S. pneumoniae and 28 episodes of M. catarrhalis otitis media. Carriage of nontypable H. influenzae (95% vs. 65%, P less than 0.001), S. pneumoniae (91% vs. 52%, P less than 0.005) and M. catarrhalis (86% vs. 52%, P less than 0.001) increased significantly during episodes of otitis media compared with healthy periods. The quantity of nontypable H. influenzae, S. pneumoniae and M. catarrhalis in nasopharyngeal secretions also increased during active infection compared with healthy periods: 3.0 vs. 2.0, P less than 0.005; 3.2 vs. 2.1, P less than 0.001; and 3.3 vs. 2.5, P less than 0.01, respectively. At the same time, nonpathogens of the resident flora, in particular viridans streptococci, declined in carriage: 65% vs. 22%, P less than 0.001. These data suggest that respiratory pathogens become relatively more important in the microenvironment of the nasopharynx during episodes of otitis media. Furthermore the absence of a middle ear pathogen in a nasopharyngeal culture strongly suggests that the pathogen is not present in the middle ear space (negative predictive value greater than 0.96).

The rectus abdominis muscle flap in a combined abdominovaginal repair of difficult vesicovaginal fistulae. A report of three cases

Conventional repairs had been tried on three patients suffering from vesicovaginal fistulas after abdominal hysterectomies. Separate vaginal and abdominal approaches had been tried and had resulted not only in failure but also in tissue loss and fibrosis. A final synchronous vaginoabdominal approach using a rectus abdominis muscle flap was used successfully in all three patients.

Ethanol sulfation by the pulmonary ethanol metabolizing system (PET)

Rat lung slices incubated in a Krebs Ringer bicarbonate buffer metabolized ethanol by sulfocunjugation at a rate of about 500 mumoles/g x hr when the ethanol concentration was 11 mM. Tissue slices from dog and rabbit lung also were able to metabolize this alcohol showing similar time curves and rates. In all cases ethanol metabolism showed a dependence on the concentration of ethanol which is typical of allosteric enzymes. The calculated Hill coefficient was between 1.69 and 2.07 in the three species studied. Sulfoconjugation of ethanol by rat lung slices showed a Km for ethanol of 26.59 mM and a Vmax of 11,357 mumoles/g x hr. The Km for ethanol determined with dog lung slices was 20.93 mM and Vmax was 8,052 mumoles/g x hr. In the case of rabbit lung, Km for ethanol was 20.15 mM whereas Vmax was 17,379 mumoles/g x hr. Preliminary evidence would seem to indicate that the human lung is also able to metabolize ethanol by conjugation with sulfate. These results suggest that the lung is endowed with a remarkable potential to metabolize ethanol by sulfoconjugation. In vivo, however, sulfoconjugation may be limited by substrate availability.

Graph-set analysis of hydrogen-bond patterns in organic crystals

A method is presented based on graph theory for categorizing hydrogen-bond motifs in such a way that complex hydrogen-bond patterns can be disentangled, or decoded, systematically and consistently. This method is based on viewing hydrogen-bond patterns topologically as if they were intertwined nets with molecules as the nodes and hydrogen bonds as the lines. Surprisingly, very few parameters are needed to define the hydrogen-bond motifs comprising these networks. The methods for making these assignments, and examples of their chemical utility are given.