Shigella bacteremia in adults. A report of five cases and review of the literature.

Shigella bacteremia is rare, occurring mainly in children. We describe five adult patients with Shigella bacteremia and review data on 22 cases reported in the English-language medical literature. Eighteen (67%) of 27 patients had either an underlying condition or were aged older than 65 years. Most patients had clinical signs of acute febrile gastroenteritis. However, in six patients, the organism was not isolated from stool. Species isolated from blood included Shigella flexneri in 11 patients, Shigella sonnei in eight, and Shigella boydii and Shigella dysenteriae in one patient each. Isolation of the bacterium from blood only was associated with a high mortality rate, in contrast to its isolation both from blood and stool. It is suggested that blood cultures should be obtained from elderly or immunocompromised patients with acute febrile gastroenteritis to detect shigellemia as well as bacteremia caused by other enteric pathogens, such as Salmonella or Campylobacter.

Bacteremia in adult diabetic patients.

OBJECTIVE: To compare the microbiology, sources, complications, and outcome of bacteremia in diabetic and nondiabetic patients. RESEARCH DESIGN AND METHODS: A prospective study was conducted of all episodes of bacteremia in hospitalized diabetic and nondiabetic patients. The study consisted of patients greater than or equal to 18 yr of age with bacteremia detected within a 19-mo interval. RESULTS: We compared 124 episodes of bacteremia in 119 diabetic patients to 508 episodes in 480 nondiabetic patients. Diabetic patients were older than nondiabetic patients (median age 74 vs. 68 yr, P = 0.0001). In patients with an indwelling urinary catheter and bacteremic urinary tract infection, the percentage of Klebsiella in diabetic patients was 60% (6 of 10) and in nondiabetic patients was 17% (4 of 23, P = 0.04). In patients without an obvious source of bacteremia, the percentage of staphylococcal isolates in diabetic patients was 29% (10 of 35) and in nondiabetic patients was 14% (24 of 176, P = 0.04). Staphylococci were a common cause of bacteremic infections of the extremities in diabetic patients (12 of 19, 63%) and nondiabetic patients (20 of 50, 40%). Septic shock was the only complication that was more common in diabetic patients. The mortality in diabetic and nondiabetic patients was 28 and 29%, respectively. CONCLUSIONS: Our results represent elderly patients with non-insulin-dependent diabetes mellitus. In this group, empirical treatment for suspected bacteremic urinary tract infection in patients with a urinary catheter should include coverage for Klebsiella. Empiric treatment for suspected bacteremia of unknown origin or caused by infection of the extremities should include an antistaphylococcal drug. The prognosis of bacteremia in diabetic and nondiabetic patients was similar.

High-molecular-weight forms of tyrosinase and the tyrosinase-related proteins: evidence for a melanogenic complex.

Tyrosinase, tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2, (TRP-2, dopachrome tautomerase) were shown by immunoblotting and enzyme assays to copurify from extracts of Cloudman S91 melanoma cells. Antibodies to TRP-1 and TRP-2 immunoprecipitated tyrosinase activity, suggesting a stable interaction (complex) among these proteins. The tyrosine hydroxylase activity of tyrosinase was reduced in the complexed form; treatment with Triton X-100 dissociated the complex and activated the tyrosinase present within it. To further study this complex, we employed sucrose gradient density centrifugation of extracts from cultured murine melanocytes. Tyrosinase, TRP-1, and TRP-2 all existed in high molecular weight "multimers" of approximately 200 to > 700 kilodaltons. Extraction of cells with buffers containing the detergent CHAPS preserved the high molecular weight multimers; Triton X-100 caused their dissociation into monomers. Low pH, low ionic strength, and millimolar concentrations of calcium ions favored the maintenance of multimers. The results of this study demonstrate that the participation of tyrosinase, TRP-1, and TRP-2 in a multimeric complex could have important physiologic consequences, and raise the possibility that some of the well-known interactions between coat color genes may be explained by intermolecular interactions between the gene products.

Excess mortality in women with hospital-acquired bloodstream infection.

PURPOSE: We examined the outcomes of bloodstream infection in men and in women and whether any sex-related differences were explained by underlying disorders, severity of disease, or clinical management. SUBJECTS AND METHODS: Using a prospectively collected database, we compared in-hospital mortality in men and women. We used multivariable logistic regression analysis to test whether sex-related differences could be due to potential confounders. RESULTS: Of 4250 patients with bloodstream infections, 1750 (41%) had hospital-acquired infections. The overall case fatality was 31% (625 of 2032) in women and 29% (631 of 2218, P = 0.1) in men. However, 43% (325/758) of the women with hospital-acquired infections died, compared with 33% (327/992) of the men (P = 0.0001). In a multivariate analysis, female sex was associated with greater mortality in patients with hospital-acquired infections (odds ratio = 1.7; 95% confidence interval: 1.1 to 2.6). The excess mortality in women was mainly seen in patients with major underlying disorders (fatality rate of 45% [234 of 525] in women vs. 32% in men [234 of 743, P = 0.0001). CONCLUSIONS: Mortality in women with hospital-acquired bloodstream infections is substantially greater than in men. The excess mortality was concentrated in women with severe underlying disorders, suggesting that sepsis might have accentuated differences in the outcome of underlying disorders in women.

Intimo-intimal intussusception and other unusual manifestations of aortic dissection.

Four cases with unusual aortic dissection found unexpectantly at the time of operation, and their aortographic and anatomic findings and surgical treatment are described. One of the patients had a type I aortic dissection with intimo-intimal intussusception and another had a type I dissection with one portion of the intimal wall unidentifiable up to the origin of the innominate artery. One patient had a type III dissecting aneurysm with retrograde dissection into the aortic arch and ascending aorta, and the fourth patient had a dissecting aneurysm involving the ascending aorta and the innominate, right common carotid, and right vertebral arteries with a re-entry at the aortic arch.

Thrombocytosis after pneumonia with empyema and other bacterial infections in children.

Thrombocytosis is seen in association with many conditions, including infectious diseases. We studied thrombocytosis after severe bacterial infections, particularly pneumonia with empyema in children. A systematic survey of the phenomenon was conducted. Twenty-seven children admitted for pneumonia with empyema were studied. Thrombocytosis (platelet counts greater than 500 x 10(3)/microliters) was present in 92.5%. Platelet counts reached their maximum at 15.1 +/- 3.7 days (range, 7 to 25) and declined to normal after 3 weeks of illness. Compared with a healthy control group, significant thrombocytosis, but of lower incidence, was also noted in children with lobar pneumonia without pleural effusion, bacterial meningitis and osteomyelitis. Platelet functions were examined in seven of the children but no abnormalities were observed. Bone marrow aspiration of three children with pneumonia and empyema showed megakaryocytic hyperplasia. We found no correlation between thrombocytosis, neutrophilia, fever, the clinical course, complications, prognosis or treatment. Neither thromboembolic nor hemorrhagic phenomena were observed.

Clinical and laboratory findings of spotted fever in Israeli children.

In a prospective study of 70 Israeli children with spotted fever the major clinical features were fever (100%), skin rash (98.5%), myalgia (54%) and vomiting (40%). Thrombocytopenia (75%) and hyponatremia (62.5%) were common, but were not associated with increased mortality. Antibodies to Rickettsia conorii were detected by the indirect immunofluorescent antibody assay. In one patient Rickettsia was grown from blood. Contacts with dogs were reported in 17 of 40 patients questioned, and in only 2 was a canine tick bite obvious. Hospitalization was required in 11 (16%) patients. There was 1 fatality. The rickettsia responsible for spotted fever in Israel appears to be an antigenic variant of R. conorii. Early recognition and treatment of this disease permits rapid eradication of the rickettsiae and facilitates complete recovery.

A prospective study of Gram-negative bacteremia in children.

BACKGROUND: Hospital- and community-acquired Gram-negative bacteremia is a significant cause of mortality and morbidity in pediatric medical centers. Gram-negative organisms are isolated in > 50% of pediatric patients with bacteremia. OBJECTIVES: To analyze clinical and epidemiologic variables associated with Gram-negative bacteremia in a tertiary children's medical center. METHODS: A 6-year prospective study of children with Gram-negative bacteremia in a tertiary care children's medical center in Israel. RESULTS: Three hundred seventy-four episodes of Gram-negative bacteremia were studied during 6 years. The predominant isolates were Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli, which accounted for 109, 81 and 79 episodes (26, 20 and 19%), respectively. Of all episodes 43% occurred in neonates and infants younger than 2 years and 47% were hospital-acquired. Underlying conditions mainly acute leukemia and lymphoma, were present in 55% of the patients. Urinary tract infection followed by lower respiratory tract infection were the most common identified sources of bacteremia. Central intravenous catheters were associated with 53% of the episodes. The crude mortality was 11.4%. Increased mortality was significantly associated with acute leukemia, neutropenia, hospital-acquired infections and previous corticosteroid therapy (P = 0.03, 0.003, 0.006 and 0.01, respectively). Increased antibiotic resistance of hospital-acquired vs community-acquired isolates was noted; 44 to 77% resistance of nosocomial Klebsiella and Enterobacter sp. to second and third generation cephalosporins and 18% were resistant to amikacin. CONCLUSIONS: Klebsiella pneumoniae is currently the most common organism causing Gram-negative bacteremia in children. Because of the relatively high resistance of Gram-negative organisms to second and third generation cephalosporins, we suggest that empiric antibiotic therapy for Gram-negative bacteremia include a combination of an aminoglycoside and an anti-Pseudomonas beta-lactam.

Prognostic significance of the neutrophil count in immunocompetent patients with bacteraemia.

To examine the prevalence of neutropaenia in immunocompetent, bacteraemic patients, and whether it carries an independent risk for mortality, we surveyed 2096 bacteraemic patients without malignant diseases, and who were not receiving cytotoxic drugs. The granulocyte count on the day of the first positive blood culture was < 1 x 10(9) cells/l in 33 patients (1.7%, group 1); 1.0-4.0 x 10(9) cells/l in 154 patients (7.9%, group 2); 4.0-8.0 x 10(9) cells/l in 564 patients (29%, group 3); 8.0-20.0 x 10(9) cells/l in 1034 patients (53%, group 4); and > 20.0 x 10(9) cells/l in 163 patients (8.4%, group 5). The mortality rates in the five groups were 39.4%, 18.8%, 18.1%, 25.7% and 25.8%, respectively (p = 0.0001). The main pathogens in group 1 were Staphylococcus aureus in 25% of patients and Pseudomonas sp. in 23%. Mortality in group 1 patients was higher than in the other patients (odds ratio 1.4, 95% CI 1.1-1.9]. Mortality was also significantly higher in group 2 patients with high blood urea nitrogen. The percentage of neutropaenia, septic patients without known risk factors for neutropaenia is small, but their mortality is high. Overall mortality in patients with relative neutropaenia (1.0-4.0 x 10(9) cells/l) is low, but a subgroup of patients with high blood urea nitrogen is at considerable risk for a fatal outcome. High leucocyte counts are also a marker of increased risk for mortality, but this association is not an independent prognostic factor.

Esophageal carcinoma: an aggressive approach.

During a 3-year period, 45 patients with esophageal carcinoma (18 of the lower and 27 of the middle third) underwent esophagectomy and esophagogastrostomy. All patients were considered to be in Stage I and Stage II preoperatively, but at the time of operation, 66% were found to have Stage III disease. All patients underwent mobilization of the stomach through a laparotomy, and resection of the esophagus and reconstruction of the continuity of the gastrointestinal tract through a separate right lateral thoracotomy incision. Following operation, 22 patients (10, Stage I and II and 12, Stage III) received no radiotherapy and 23 patients (5, Stage I and II and 18, Stage III) received radiotherapy. Two patients died in the immediate postoperative period, for a surgical mortality of 4.8%. Because of the acceptable survival and enhancement of quality of life, esophagectomy and esophagogastrostomy should be offered not only to Stage I and II patients with esophageal carcinoma but also to selected patients with Stage III disease and those with lower and middle third esophageal lesions.

Low-contrast letter charts to detect subtle optic [corrected] neuropathies.

We performed visual contrast sensitivity testing with Regan's low-contrast letter charts on 30 patients with optic neuropathies and good Snellen visual acuity. Results of this testing were compared with color vision and the presence of an afferent pupillary defect. Regan's low-contrast letter charts were found to be 93% sensitive for detecting subtle optic neuropathies, with the apparent false-negative findings being readily explainable. Color vision testing was abnormal in only 49% of eyes with known optic neuropathies.

Right aortic arch with aberrant left subclavian artery: symptomatic in adulthood.

A 42 year old black woman presented initially with symptoms of acute aortic dissection. She subsequently had symptoms of esophageal obstruction that were proved aortographically to be due to right aortic arch with an aberrant left subclavian artery. Relief of the esophageal obstruction was achieved only after dividing the aortic arch posteriorly and freeing the trachea and esophagus from the surrounding structures.

The effect of topical ceftazidime on pseudomonas keratitis in rabbits.

Ceftazidime is a beta-lactam antibiotic highly effective against Pseudomonas aeruginosa infection. Using a rabbit model of Pseudomonas keratitis, 10(3) bacteria (in 20 microliters) were injected unilaterally into the corneal stroma of albino rabbits. Twenty-six hours after inoculation, topical Ceftazidime (50 mg/ml) drops were administered for 48 h, following which the corneal tissue was cultured. Eighteen of 20 corneal cultures (90%) from rabbits treated with Ceftazidime drops were negative. In comparison, all untreated control group cultures showed florid bacterial growth. These results suggest that topical Ceftazidime may be a useful agent in the treatment of P. aeruginosa keratitis.

Thromboembolic complications of ventriculoatrial shunts.

Ventriculoatrial shunts were first developed in the 1940s and shortly thereafter became the treatment of choice for noncommunicating hydrocephalus. Although the mortality rate for noncommunicating hydrocephalus has fallen from 80% to 20%, ventriculoatrial shunts continue to have major life-threatening complications such as thromboemboli, infection, and shunt malfunction. This report presents the cases of two adult hydrocephalic patients who developed pulmonary emboli and sepsis after being treated with ventriculoatrial shunts. One patient, whose complications were not recognized until late in the course, died of pulmonary hypertension and right heart failure despite removal of the shunt and aggressive medical therapy. Complications in the second patient were discovered early, the shunt was removed, and intravenous antibiotics were used for weeks to combat sepsis and bacterial endocarditis.

Postcircumcision urinary tract infection.

The possible association of urinary tract infection (UTI) with ritual circumcision on the eighth day of life was studied by analyzing the epidemiology of urinary tract infections during the first year of life in 169 children with UTI (56 males and 113 females) born in Israel from 1979 to 1984. Forty-eight percent of the episodes of UTI occurring in males appeared during the 12 days following circumcision, and the increased incidence during that period was highly significant. The median age of the males at the time of the UTI was 16 days, compared with seven months in females. Ritual Jewish circumcision as practiced in Israel may be a predisposing factor for UTI during the 12-day period following that procedure.