Experimental infection of the skin in the hamster simulating human impetigo. III. Interaction between staphylococci and group A streptococci.

The interaction between staphylococci and Group A beta hemolytic streptococci in mixed lesions was investigated in an experimental impetigo model. A strain of staphylococcus of phage Type 71, which has been shown in vitro to produce a bacteriocin for streptococci and other Gram-positive organisms, eliminates or reduces Group A streptococci in mixed lesions. In contrast, staphylococcal strains of phage Types 75 and 81, which do not produce a demonstrable bacteriocin in vitro, exhibit no such effect. Some variation was noted in the in vivo response of two different streptococcal M Types to the bactericidal effect of phage Type 71 staphylococci. Bacterial antagonism is more pronounced when staphylococci and streptococci are injected simultaneously into animals than when staphylococci are superimposed on preexisting streptococcal lesions. Marked variations were found in the numbers of viable streptococci (colony-forming units) recovered from individual lesions containing identical mixtures of streptococci and phage Type 71 staphylococci. The frequency of a demonstrable bactericidal effect was related to the number of streptococci injected. With small inocula of streptococci, the tendency towards an all-or-none effect was particularly striking. No evidence of selection of streptococcal or staphylococcal mutants which might explain this phenomenon was obtained. These observations suggest that the bactericidal effect of phage Type 71 staphylococci on other Gram-positive organisms, previously demonstrated in vitro, appears to operate also in vivo.

Bactericidal substance from Staphylococcus aureus. Biological properties.

A bactericidal substance previously isolated from phage type 71 Slaphylococcus aureus has been further identified and characterized. Staphylococci belonging to phage type 71 produce the substance in higher titers than staphylococci lysed by other phages in group II in addition to phage 71. Other staphylococci do not produce the bactericidal substance. The bactericidal substance shares several of the properties of bacteriocins but differs from this group of antibiotic substances in some respects. A combination of ammonium sulfate fractionation and gel filtration on a Sephadex G-100 column resulted in considerable degree of purification of the bactericidal substance. The substance is a previously unrecognized product of S. aureus and is distinct from other extracellular products of this organism.

Group A streptococcal bacteriocin. Production, purification, and mode of action.

A bacteriocin, streptocin A, was isolated from the supernatant fluid of tryptic soy broth cultures of Group A streptococcus strain FF-22. Evidence was obtained which supports the view that the failure to recover active streptocin A after growth of the producer strain in certain fluid media is due to the inactivation of the bacteriocin by concomitantly synthesized streptococcal proteinase. The bacteriocin was purified 139-fold and the active product appeared to be of uniform size, having a molecular weight of approximately 8,000. Streptocin A was bactericidal, but not lytic, for a susceptible Group A streptococcus and the lethal effect was markedly temperature dependent. The bacteriocin inhibited the synthesis of DNA, RNA, and protein, and also prevented the uptake and incorporation of glucose by the sensitive cells. Degradation of RNA occurred, but appeared to be less than that produced by a staphylococcal bacteriocin. This effect may be due to differences in the killing potency of the two bacteriocins in preparations having similar inhibitory activity when measured by lawn culture assays.

Natural history of impetigo. II. Etiologic agents and bacterial interactions.

Intensive observations on 37 children in a population with endemic skin infections provided an opportunity to study the interrelationships between and the significance of the bacterial genera commonly associated with impetigo. Cultures of the respiratory tract, three normal skin sites, and lesions, when present, were taken three times weekly from July to October 1969. Impetigo developed in all 37 children. Group A streptococci alone were recovered from 21% of 361 lesions, Staphylococcus aureus alone from 8%, Staphylococcus epidermidis alone from 5% and mixtures of streptococci and staphylococci from 61%. Vesicular or pustular lesions were more often pure streptococcal than pure staphylococcal. Streptococci alone were more often recovered from early stage lesions rather than from later ones. The pure staphylococcal lesions characteristically occurred early in the season whereas streptococcal or mixed lesions had later peaks.Serial observations on 74 lesions revealed longer persistence of streptococci than staphylococci in mixed lesions. In 85% of the instances the same streptococcal serotype was recovered repeatedly from an individual lesion, whereas staphylococcal types changed in 57% of instances. Phage type 75 accounted for the majority of staphylococcal isolates from all sites, whereas phage type 54 was recovered only from skin lesions. In contrast to streptococci, the site sequence of staphylococcal spread was from the nose to normal skin to skin lesions. These studies reveal important differences in the migration of staphylococci (as compared with streptococci) to various body sites and suggest a subsidiary role for staphylococci in nonbullous impetiginous lesions yielding both organisms.

Natural history of impetigo. I. Site sequence of acquisition and familial patterns of spread of cutaneous streptococci.

The appearance on and spread of Group A streptococci among different body sites in relationship to the development of impetigo were studied prospectively in 31 children in five families. During July and August 1969 intensive clinical, bacteriological, and serological observations were made, including cultures taken at least every other day. In individual children, site sequence of spread of Group A streptococci was from normal skin to lesions and finally to respiratory tract. Streptococci were recovered from normal skin before development of lesions (mean interval of 10 days) in 74% of episodes. Recovery of streptococci from nose and throat followed (by means of 14 and 20 days, respectively) skin acquisition of streptococci (97% of episodes) and lesions (74% of episodes).Distribution of positive normal skin sites among wrist, ankle, and back was similar (28-37%) although 62% of lesions were on the legs. Recovery of a serotype from normal skin was associated with a high risk (76%) of subsequent development of lesions due to that type. New streptococcal serotypes usually entered a family during the peak or decline of a preceding serotoype with a tendency of one to predominate. Among family members the mean interval from index to secondary skin acquisition of streptococci was 4.8 days, but 21 days elapsed from first appearance to last acquisition of skin disease. In the population as a whole, streptococci were recovered in high frequency from normal skin before the increase in prevalence of lesions and also later in the fall when cutaneous infections were absent.

Epidemiological evaluation of acute gastroenteritis and therapeutic approaches in Middle East Countries.

OBJECTIVE: Gastroenteritis represents with respiratory tract infection the most common infectious disease syndrome of humans in developing countries. Gut microbiota regional variation and dysbiosis play a crucial role in triggering and worsening this devastating GI disease. MATERIALS AND METHODS: With this manuscript, we want to explore and emphasize the critical aspect of acute gastroenteritis in Middle-East Countries and its correlation with the clinical aspect of gut microbiota modification and intestinal homeostasis. RESULTS: Approximately 1 of 50 children born each year in developed nations is hospitalized for acute gastroenteritis sometime during childhood. The highest rate of illness occurs in children between 3 and 24 months of age. The common causes of diarrhea are infections with viruses and bacteria, diarrhea due to a systemic infection other than gastrointestinal, diarrhea associated with antibiotic administration, and feeding related diarrhea. The single most common diarrheal disorder observed in the Emergency Department and general practice is viral gastroenteritis. In particular, Rotavirus is the cause of more than 2 million hospitalizations and over half a million deaths from acute GE in infants and young children. This burden produces also direct and indirect economic costs. The use of probiotics to counterbalance commensal dysbiosis is emerging as a standard medical practice in these countries. CONCLUSIONS: In this scenario, one of the most interesting aspects is that probiotics and gut microbiota modulation could deeply improve the prevention and treatment of this devastating GI pathology. At the same time, vaccination might represent a cost-effective strategy to reduce the health and economic burden of some pathogens, such as rotavirus.

Adherence to physicians' instructions as a factor in managing streptococcal pharyngitis.

Adherence to physicians' instructions, including taking medications as prescribed, is essential for the proper treatment of streptococcal pharyngitis and the prevention of rheumatic fever. Nonadherence can be in many forms, including failure to have prescriptions filled, omission of doses, errors in dosing or administration time, and premature discontinuation of medication. Adherence is dependent on the physician, the patient, the illness, and the medication. Proper communication by the physician and prescribing inexpensive medications that can be taken once or twice daily are simple, yet important actions that improve adherence.

Group B streptococcal colonization in prepubertal children.

Colonization of prepubertal boys and girls with group B streptococci was studied prosepctively for one year. Throat, anal canal, and vaginal cultures were obtained from 415 children not receiving antimicrobics. The over-all colonization rate at any site was 11.3% and did not vary with age, sex, or season. Streptococci were recovered most commonly from the anal canal. Throat colonization was comparable in boys and girls. A total of 71 sites were positive for the organism in the 47 colonized children. Serotype Ia was the most common (41% of isolates). Types II and III accounted for 24% and 20%, respectively. Colonization at more than one site occurred in 20 children and in two of these children, different serotypes were recovered from different sites.

Treatment of acute streptococcal pharyngitis and prevention of rheumatic fever: a statement for health professionals. Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease of the Council on Cardiovascular Disease in the Young, the American Heart Association.

Primary prevention of acute rheumatic fever is accomplished by proper identification and adequate antibiotic treatment of group A beta-hemolytic streptococcal (GAS) tonsillopharyngitis. Diagnosis of GAS pharyngitis is best accomplished by a throat culture. Penicillin (either oral penicillin V or injectable benzathine penicillin) remains the treatment of choice, because it is cost effective, has a narrow spectrum of activity, has long-standing proven efficacy, and GAS resistant to penicillin have not been documented. Various macrolides, oral cephalosporins, and other beta-lactam agents are acceptable alternatives, particularly in penicillin-allergic individuals. The individual who has had an attack of rheumatic fever is at very high risk of developing recurrences after subsequent GAS pharyngitis and needs continuous antimicrobial prophylaxis to prevent such recurrences (secondary prevention). The duration of prophylaxis depends on the number of previous attacks, the time lapsed since the last attack, the risk of exposure to streptococcal infections, the age of the patient, and the presence or absence of cardiac involvement. Penicillin is again the agent of choice for secondary prophylaxis, but sulfadiazine or erythromycin are acceptable alternatives in penicillin-allergic individuals. This report is an update of a 1988 statement by this committee. It expands on the previous statement, includes more recent therapeutic modalities, and makes more specific recommendations for the duration of secondary prophylaxis.

Violaceous discoloration in pneumococcal cellulitis.

Two patients with periobital cellulitis, one of whom also had buccal cellulitis, had violaceous discoloration of the skin. Blood cultures from both patients yielded Streptococcus pneumoniae. Therefore, pneumococci should be considered, in addition to Haemophilus influenzae, as possible causes of cellulitis with violaceous or bluish-red discoloration.

Comparison of cefpodoxime proxetil and cefixime in the treatment of acute otitis media in infants and children. Otitis Study Group.

OBJECTIVE: To compare the use of once-a-day cefpodoxime proxetil to once-a-day cefixime in the treatment of acute suppurative otitis media. DESIGN: Randomized, multicenter, investigator-blinded. SETTING: Outpatient. PATIENTS: A total of 368 patients (age 2 months to 17 years) were randomized to receive either cefpodoxime or cefixime in a 2:1 ratio (245 cefpodoxime, 123 cefixime); 236 patients (155 cefpodoxime, 81 cefixime) were evaluable for drug efficacy. INTERVENTIONS: Patients received either cefpodoxime proxetil oral suspension (10 mg/kg/day, once daily for 10 days) or cefixime oral suspension (8 mg/kg/day, once daily for 10 days). MAIN OUTCOME MEASURES: Clinical evaluations were performed before treatment (study day 1), at an interim visit (study day 3 through 6), at the end of therapy (study day 12 through 15), and at final follow-up (study day 25 through 38). Microbiologic evaluations were performed at enrollment and whenever appropriate thereafter. RESULTS: End-of-therapy clinical cure rates in evaluable patients were 56% for the cefpodoxime group and 54% for the cefixime group. Clinical improvement rates were 27% for both groups. Clinical response rates were not significantly different between treatment groups (P = .541; 95% confidence interval = -8.1%, 15.2%). At long-term follow-up, 17% of patients in the cefpodoxime group and 20% in the cefixime group had a recurrence of infection. Drug-related adverse events (eg, diarrhea, diaper rash, vomiting, rash) occurred in 23.3% of cefpodoxime-treated patients and 17.9% of cefixime-treated patients (P = .282). CONCLUSIONS: These findings suggest that cefpodoxime proxetil administered once daily is as effective and safe as cefixime given once daily in the treatment of acute suppurative otitis media in pediatric patients.

Sulbactam/ampicillin in paediatric infections.

The emergence and spread of ampicillin-resistant Haemophilus influenzae type b strains have led to a sharp reduction in the use of ampicillin, or the addition of chloramphenicol, in the initial therapy of serious childhood infections. In some instances, third generation cephalosporins are used instead. The combination of ampicillin with sulbactam restores the former usefulness of ampicillin and extends its spectrum of activity to include normally ampicillin-resistant Staphylococcus aureus. Sulbactam/ampicillin should be useful in treating bacterial meningitis. It is more effective than third generation cephalosporins against Listeria and enterococci, and is more effective than ampicillin against Enterobacteriaceae. The combination also holds promise as a treatment for soft tissue, bone and joint infections in children.

Pharyngitis/tonsillitis: European and United States experience with cefpodoxime proxetil.

Most authorities continue to recommend penicillin as the treatment of choice for group A streptococcal pharyngitis. If penicillin is used, 10 days of treatment are necessary to achieve a clinical and bacteriologic cure. The usually recommended penicillin V dose is 250 mg (400,000 IU) three times daily. Twice daily dosing is acceptable to some authorities if compliance is good. However, oral penicillin fails to eradicate group A streptococci from the pharynx in up to 17% of cases; in some studies 30% failure rates have been reported. Several European and United States studies indicate that a variety of oral cephalosporins, when used for 10 days, are significantly superior to penicillin V in eradicating group A streptococci from the pharynx. For example cefpodoxime proxetil given twice daily for 10 days is comparable to penicillin V given three times daily for 10 days in achieving a clinical cure and appears to be significantly superior to penicillin in eradicating group A streptococci from the pharynx. Preliminary studies from Europe and the United States strongly suggest that 5-day therapy with cefpodoxime (or other selected oral cephalosporins) is at least as effective, clinically and microbiologically, as 10-day therapy with penicillin V. Further clinical trials are warranted to confirm the adequacy of 5-day treatment and to assess the efficacy of cefpodoxime and other agents in preventing rheumatic fever.

Candidemia in children with central venous catheters: role of catheter removal and amphotericin B therapy.

We reviewed retrospectively 31 cases of candidemia in children with central venous catheters. Infection rate was significantly higher in 1- to 4-year-old children with central venous catheters. Infection rate was significantly higher in 1- to 4-year-old children than in other age groups (8.4% vs. 2.2%; P less than 0.05). Serious sequelae occurred in 11 (35%) cases and included fatal outcome (5 instances), Candida endocarditis (2), renal abscesses, meningitis, arthritis and osteomyelitis (1 each). Complications were significantly more common in infants than in older children (P less than 0.05) and appeared 3 to 52 days after the first positive blood culture (mean, 16 days). In fatal cases catheters were left in place a significantly greater number of days than in nonfatal cases (P less than 0.05). A literature review identified 43 additional cases of catheter-related candidemia described in 11 series. The rate of Candida infection in the group as a whole was 2.7%. Patients treated with catheter removal plus amphotericin B had a significantly higher cure rate then patients treated with catheter retention plus amphotericin B (P = 0.009). Prompt catheter removal remains crucial in the treatment of catheter-related candidemia.

Increasing Enterobacter bacteremia in pediatric patients.

Thirty-two episodes of Enterobacter bacteremia were identified in 30 patients at Children's Hospital of Michigan between September, 1989, and November, 1992. Fifty-six percent of the episodes were nosocomial. Enterobacter accounted for 14% of all nosocomial bacteremias and was the most common Gram-negative organism causing such infections. Enterobacter cloacae was the most commonly isolated species (72%). Twenty-nine (97%) patients had underlying risk factors for infection, including central venous catheters in 22. The susceptibility pattern of 46 Enterobacter isolates from blood during the same study period showed high resistance to extended spectrum penicillins and third generation cephalosporins but low resistance to aminoglycosides and trimethoprim-sulfamethoxazole (TMP/SMX). Resistance to third generation cephalosporins increased throughout the study period and was higher in patients who had received these agents during the previous month. In situations where there is a high frequency of Gram-negative bacteremias with organisms resistant to third generation cephalosporins, we suggest that initial therapy be a combination of a beta-lactam agent and an aminoglycoside or TMP/SMX.

Cefpodoxime proxetil vs. penicillin V in pediatric streptococcal pharyngitis/tonsillitis.

This multicenter, randomized, parallel treatment, observer-blinded study was designed to evaluate the safety and efficacy of cefpodoxime proxetil (5 mg/kg twice daily for 10 days) compared with penicillin V (13.4 mg/kg three times daily for 10 days) for treatment of Group A streptococcal pharyngitis and tonsillitis in pediatric patients. Clinical and microbiologic results were evaluated before therapy, during therapy (Study Days 3 to 5), at the end of therapy (Study Days 14 to 18) and at long term follow-up (Study Days 30 to 32). Both drugs were well-tolerated in 578 patients evaluable for safety. Mild gastrointestinal complaints were noted in 6.7% of 386 cefpodoxime-treated patients and in 5.2% of 192 penicillin-treated patients. In 413 patients evaluable for efficacy, both treatment regimens resulted in comparably favorable clinical outcome; cure rates were 83.8% for 275 cefpodoxime-treated patients and 77.5% for 138 penicillin-treated patients. However, eradication of S. pyogenes at end of therapy was significantly higher with cefpodoxime (93.1%) than with penicillin (81.2%) (P < 0.01). Cefpodoxime proxetil provides an effective alternative to penicillin V for the treatment of streptococcal pharyngitis and tonsillitis.

Use of electrophoretic karyotyping in the evaluation of Candida infections in a neonatal intensive-care unit.

OBJECTIVE: To evaluate a possible common-source outbreak of Candida infections in the neonatal intensive-care unit. Systemic Candida infections increased from 6 to 11 cases (0.71 to 1.34 per 1,000 patient-days). In addition, Candida parapsilosis infections increased from 1 in 1992 to 10 in 1993. DESIGN AND SETTING: Tertiary-care, teaching, pediatric institution with a 40-bed neonatal intensive-care unit (NICU). Clinical characteristics, associated conditions, and antimicrobial therapy were obtained from the medical records of all NICU patients with positive blood cultures for Candida during 1992 and 1993. Nineteen Candida isolates from 15 infants were studied retrospectively using contour-clamped homogeneous electric-field (CHEF) electrophoresis. RESULTS: CHEF revealed eight karyotypes of C parapsilosis. Five isolates recovered from four patients shared one karyotype. The remaining isolates from seven infants all had distinctly different karyotypes. CONCLUSIONS: The evidence was insufficient to implicate a single source of infection, even though four patients in the same unit had identical strain types. However, identical strains of C parapsilosis were associated geographically, suggesting that nosocomial acquisition of C parapsilosis through indirect patient contact in the NICU was possible. The CHEF technique yields unique patterns that may be used to delineate clinical isolates and to study the molecular epidemiology of candidal infections.

Resurgence of congenital syphilis.

As a result of the alarming increase in primary and secondary syphilis in the United States, congenital syphilis has resurged in many areas, including Detroit. Several maternal risk factors have been identified as contributing to the increase in congenital syphilis, the most important of which are poor prenatal care and the trading of sex for illicit drugs, specially "crack" cocaine. Contact tracing programs are currently ineffective. To prevent the continuing increase in congenital syphilis, a comprehensive prenatal care program starting in early pregnancy is essential. STS should be determined during pregnancy and may be required more than once in high-risk mothers. Results of STS must be verified before infants are discharged from nurseries. Obstetricians, neonatologists, pediatricians, and general practitioners should be more aware of the problem of congenital syphilis and the need for early intervention and treatment.

Cefotaxime use in pediatric infections.

Cefotaxime has been used extensively in many pediatric centers in the United States for the past 10 or more years. Its main usage has been for the treatment of various serious bacterial infections in pediatric patients, primarily meningitis and sepsis. It has also been used to treat intraabdominal, urinary tract, soft tissue, bone, and joint infections. Although there has been a marked reduction in the incidence of invasive Haemophilus influenzae type b infections following the introduction of effective vaccines, cefotaxime remains very useful against the other common pathogens causing serious infections in pediatric patients. The increasing number of pneumococci resistant to penicillin and third-generation cephalosporins has created a new challenge for the management of serious pneumococcal infections. In many institutions, cephalosporins in general have been overused and abused, resulting in the emergence of resistant organisms and an increasing burden on resources. The judicious use of cefotaxime and other cephalosporins should be emphasized.

Persistent cloaca in adult with satisfactory renal function.

A case of persistent and uncorrected cloaca in a twenty-five-year-old woman is presented. In spite of the anomaly not being corrected, no deterioration of her kidney function was noted. She is continent for both urine and stools. In addition to two uteri which were removed at different times, she has only one kidney on the right which is ectopic and malrotated, and an abnormal left thumb. The question of doing electromyographic studies of the pelvic muscles prior to the repair of the anomaly, together with the timing of the latter, is raised.