Showing papers by "Itzhak Brook published in 2008"

Actinomycosis: diagnosis and management.

Abstract: Actinomycosis is an uncommon, chronic bacterial infection that induces both suppurative and granulomatous inflammation. Localized swelling with suppuration, abscess formation, tissue fibrosis, and sinus drainage characterizes this disease. The infection spreads contiguously, often forming draining sinuses that extrude characteristic but not pathognomonic "sulfur granules." Infections of the oral and cervicofacial regions are most common; however, any site in the body can be infected and it often mimics malignancy. Other regions that are often affected are the thoracic and abdominopelvic, as well as the central nervous system. Musculoskeletal and disseminated disease can also be seen, albeit rarely. Prolonged antimicrobial therapy with penicillin has typically been recommended for patients with all clinical forms of actinomycosis to prevent disease recrudescence.

Current concepts in the management of Clostridium tetani infection.

Abstract: This review summarizes the microbiology, management and prevention of tetanus. Tetanus is an acute toxemic illness caused by Clostridium tetani infection at a laceration or break in the skin. It can also occur as a complication of burns, puerperal infections, umbilical stumps (tetanus neonatorum) and surgical-site infection. Tetanus is an intoxication, manifested mostly by neuromuscular dysfunction, caused by tetanal exotoxin (tetanospasmin), a potent exotoxin produced by C. tetani. It starts with tonic spasms of the skeletal muscles and is followed by paroxysmal contractions. The muscle stiffness initially involves the jaw (lockjaw) and neck and later becomes generalized. Treatment goals include interrupting the production of toxin, neutralizating the unbound toxin, controlling muscle spasms, managing dysautonomia and appropriate supportive management. Specific therapy includes intramuscular administration of tetanus immunoglobulin to neutralize circulating toxin before it binds to neuronal cell membranes. The disease can be prevented by immunization with tetanal toxoid and appropriate wound care.

Microbiology and management of abdominal infections.

Abstract: This review describes the microbiology, diagnosis, and management of intra-abdominal infections. These infections include secondary peritonitis, abdominal abscesses, and cholangitis. The infection generally occurs because enteric microorganisms enter the peritoneal cavity through a defect in the wall of the intestine or other viscus as a result of obstruction, infarction, or direct trauma. Mixed aerobic and anaerobic flora can be recovered. The predominant aerobic isolates are Escherichia coli, etc. The aerobic isolates are Escherichia coli, and enterococci, and the main anaerobic bacteria are Bacteroides fragilis group Peptostreptococcus spp. and Clostridium spp. The treatment of abdominal infection includes surgical correction and drainage of pus and administration of antimicrobials effective against both the aerobic and anaerobic pathogens.

Recovery of potential pathogens in the nasopharynx of healthy and otitis media-prone children and their smoking and nonsmoking parents.

Abstract: Objectives:Exposure to smoking is associated with colonization with pathogenic bacteria. This study investigated the frequency of isolation of potential pathogens in the nasopharynx of healthy and ...

Microbiology and Management of Neonatal Necrotizing Enterocolitis

Abstract: Necrotizing enterocolitis (NEC) is a clinical syndrome of ischemic necrosis of the bowel of multiple etiological factors that include the presence of intestinal ischemia, abnormal bacterial flora, and intestinal mucosal immaturity. Numerous reports have implied that the fecal microflora may contribute to the pathogenesis of NEC. A broad range of organisms generally found in the distal gastrointestinal tract have been recovered from the peritoneal cavity and blood of infants with NEC. The predominant organisms include Enterobacteriaceae (i.e., Escherichia coli, Klebsiella pneumoniae) , Clostridium spp., enteric pathogens (salmonellae, Coxsackie B2 virus, coronavirus, rotavirus), and potential pathogens (Bacteroides fragilis). The goals of the initial management is preventing ongoing damage, restoring hemostasis, and minimizing complications. Medical management includes withholding oral feeding, placement of nasogastric tube, abdominal decompression, paracentesis, vigorous intravenous hydration containing electrolytes and calories, support of the circulation, administration of antibiotics, and surveillance for deterioration or complications that require surgical intervention. Indications for surgery include clinical deterioration, perforation, peritonitis, obstruction, and abdominal mass. Prevention remains crucial to decrease the incidence of NEC. Preventive methods include cautious feeding regimens, the use of maternal breast milk, and the use of probiotics.

Failure to eradicate streptococci and beta-lactamase producing bacteria.

Abstract: Background: The presence of beta-lactamase-producing bacteria is associated with the failure of penicillins to eradicate Group A beta-hemolytic streptococci in patients with pharyngo-tonsillitis. This study correlated the rate of recovery of beta-lactamase-producing bacteria from healthy children with the rate of amoxicillin failure to eradicate Group A streptococci from children with acute Group A streptococcal pharyngo-tonsillitis. Patients and Methods: A total of 228 children with Group A streptococcal pharyngo-tonsillitis, treated with amoxicillin for 10 days, and 663 healthy children were evaluated in a single year. Pharyngo-tonsillar cultures were obtained from all well children and from those with pharyngo-tonsillitis before treatment and on the 12th day. Results: Amoxicillin failed to eradicate Group A streptococci from 48 of the 228 treated children (21%). Amoxicillin failure rate varied from month to month; it was high between October and May (22–32%), with the exception of April (11%); and low between June and September (8% to 12%). Beta-lactamase-producing bacteria were recovered from 226 of 663 (34%) well children. The rate of recovery of beta-lactamase-producing bacteria varied; it was also high between October and May (40–52%), with exception of April (23%), and the lowest between June and September (10–12%). Prior to their treatment, beta-lactamase-producing bacteria were recovered from 26 of the 48 (54%) children who eventually failed amoxicillin therapy, and from 28 of the 180 (16%) who did not fail (p < 0.001). Conclusions: A correlation was noted between the rate of recovery of beta-lactamase-producing bacteria in healthy children and the rate of amoxicillin failure to eradicate Group A streptococci. A high failure rate of penicillins in eradication of Group A streptococci in pharyngo-tonsillitis can serve as sensitive indicator for a high prevalence rate of beta-lactamase-producing bacteria in the community.

Ocular infections due to anaerobic bacteria in children.

Abstract: The recent increased recovery of anaerobic bacteria from children has led to greater appreciation of the role these organisms play in pediatric infections at all body sites, including the eye. In studies that employed adequate methods for recovery of anaerobes, they were isolated from approximately one-third of the children with conjunctivitis, half of the time in pure culture. The predominant recovered anaerobes were Clostridium spp., gram-negative anaerobic bacilli, and Peptostreptococcus spp. Anaerobic bacteria were also recovered from patients who wore contact lenses and developed conjunctivitis, and were reported in cases of keratitis. The most frequently recovered anaerobes were Propionibacterium spp., Peptostreptococcus spp., Clostridium spp., Prevotella spp., and Fusobacterium spp. The most frequently recovered anaerobes from dacryocystitis were Peptostreptococcus spp., Propionibacterium spp., Prevotella spp., and Fusobacterium spp. This review describes the microbiology, diagnosis, and management of ocular infections due to anaerobic bacteria in children.

Bacteremia and septicemia due to anaerobic bacteria in newborns

Abstract: The awareness of the role of anaerobic bacteria in neonatal bacteremia and sepsis has increased in recent years. The incidence of recovery of anaerobes in neonatal bacteremia varies between 1.8% and 12.5%. Of the 179 cases reported in the literature, 73 were due to Bacteroides spp. (69 were the Bacteroides fragilis group), 57 Clostridium spp. (mostly Clostridium perfringens), 35 Peptostreptococus spp., 5 Propionibacterium acnes ,3 Veillonella spp., 3 Fusobacterium spp, and 2 Eubacterium spp. Predisposing factors were perinatal maternal complications (especially premature rupture of membranes and chorioamnioni- tis), scalp abscess, prematurity, and necrotizing enterocolitis. Organisms similar to those isolated in blood were concomitantly recovered in lung aspirates and cerebrospinal and peritoneal fluids. The overall mortality noted is 26% and is highest with B. fragilis group (34%). Inappropriate choice of antimicrobial therapy was often a contributory factor to mortality. Correction of underlying pathology, surgical drainage, and the use of proper antimicrobials are critical to successful resolution of the infection. Penicillin G is the drug of choice for anaerobic infection other than one due to beta-lactamase-producing anaerobic Gram negative bacilli. Antimicrobials useful for therapy these organisms include clindamycin, metronidazole, chloramphenicol, a carbapenem, and the combination of a penicillin plus a beta-lactamase inhibitor. The awareness of the role of anaerobic bacteria in neonatal bacteremia and sepsis has increased in recent years, following improvement and simplification in the methods of growing and identification of these organ- isms. Greater adherence to proper methods of collec- tion and cultivation of these organisms has lead to their greater recovery in neonatal bacteremia. This review summarizes the microbiological, clinical features and treatment of bacteremia and caused by anaerobic bacteria in newborns.

Concurrent influenza A and group A beta-hemolytic streptococcal pharyngotonsillitis.

Abstract: Objectives A concurrent group A beta-hemolytic Streptococcus (GABHS)-influenza virus pharyngotonsillitis (PT) is generally not considered in diagnoses, even though mixed bacterial-viral infections are common in other respiratory tract infections. This report describes our experience in diagnosing a potential mixed GABHS-influenza virus PT in children. Methods Acute and convalescent antistreptolysin O (ASO) and anti-DNase B titers were obtained from 12 children with acute PT and clinical presentation that suggested viral infection, and in whom both rapid influenza A virus and rapid GABHS tests were positive. Results The children did not receive any antimicrobial therapy, and all recovered from their acute PT within 2 to 5 days and were all asymptomatic upon their return visit 3 to 4 weeks later. GABHS was recovered from 2 of the children on their return visit. However, ASO and anti-DNase B titers were not elevated in these individuals. The ASO and anti-DNase B titers determined in the first serum samples were less than the age-adjusted normal values for all of the children. However, these titers rose by at least two-dilution (0.2 logarithm) in the convalescent sera as compared with the acute ones in 4 of the 12 children (33%). One of the 8 children who had no increase in ASO and anti-DNase B titers had an acute GABHS PT 5 months later. One-year follow-up of all of the children showed no anomalies. Conclusions This report is the first to describe a concomitant GABHS and influenza A virus PT, as evident by increased ASO and anti-DNase B titers in a third of the patients who had both of these organisms detected in their upper airways.