Israel Medical Association Journal

Background: Pseudomonas aeruginosa (PSA) is an infectious pathogen associated with acute appendicitis; however, it is not consistently addressed by empirical antibiotic therapy, despite potential complications.

Objectives: To investigate the incidence, predictors, and outcomes of PSA-associated acute appendicitis in children.

Methods: We conducted a retrospective analysis involving pediatric patients who underwent acute appendicitis surgery and had positive peritoneal cultures. Clinical, microbiological, and intraoperative data were extracted from medical records.

Results: Among 2523 children with acute appendicitis, 798 (31.6%) underwent peritoneal cultures, revealing 338 positive cases (42.3%), with PSA detected in 77 cases (22.8%). Children with PSA were three times more likely to exhibit high intraoperative grading ≥ 3 (93.4% vs. 76.8%, 95% confidence interval [95%CI] 1.2–8.3, P = 0.023) and nearly four times more likely to have polymicrobial cultures (88.3% vs. 62.1%, 95%CI 1.8–8.0, P < 0.001) than those without PSA in peritoneal cultures. Duration of symptoms did not predict PSA isolation (P = 0.827). Patients with PSA had longer median hospital stays (8 days, interquartile range [IQR] 7–10) than those with other pathogens (7 days, IQR 5–9) (P = 0.004). Antibiotic treatment duration, intensive care unit admission rates, readmission, and mortality were similar between the two groups (P = 0.893, 0.197, 0.760, and 0.761, respectively).

Conclusions: PSA is a common pathogen in children diagnosed with acute appendicitis and positive peritoneal cultures. The likelihood of isolating PSA increases with high-grade intraoperative assessment and in the presence of multiple pathogens in peritoneal cultures, suggests antipseudomonal treatment.

Background: Chronic suppurative otitis media is a long-standing middle ear infection with a perforated tympanic membrane. Tympanoplasty is the mainstay of treatment. Most surgeons prefer to operate on dry ears; however, this may be difficult to achieve.

Objectives: To investigate the effect of otorrhea and positive cultures on the outcome of tympanoplasty.

Methods: This retrospective analysis reviewed patients with chronic suppurative otitis media who underwent tympanoplasty 2008–2015. Patients were divided into three groups: active discharge and bacterial growth, active discharge without bacterial growth, and no ear discharge. Surgical outcomes were compared among the groups.

Results: Among 101 patients included, 43 ears (42.6%) had discharge preoperatively, 58 (57.4%) were dry. Overall closure rate was 81.2% (82/101). Preoperative active discharge closure rate was 88.3% (38/43) and without discharge 75.9% (44/58). There were 38 positive cultures preoperatively and five negative cultures. Cultures were not obtained in 58 cases. Success rates were 89.5%, 80%, and 75.9%, respectively. No significant difference was found between patients who had positive or negative cultures before the procedure (P > 0.48) or among the three groups (P = 0.25). The most common bacteria were Pseudomonas aeruginosa (n=17), followed by Staphylococcus species (n=10). None was significantly associated with operative failure (P = 0.557). The postoperative air threshold difference was not affected by culture results (P = 0.3).

Conclusions: Tympanoplasty success rates and postoperative air threshold differences were not affected by the presence of preoperative otorrhea or positive ear cultures. Surgery can be performed even when the ear is not dry.

Background: Although indwelling catheters are increasingly used in modern medicine, they can be a source of microbial contamination and hard-to-treat biofilms, which jeopardize patient lives. At times 70% ethanol is used as a catheter-lock solution due to its bactericidal properties. However, high concentrations of ethanol can result in adverse effects and in malfunction of the catheters.

Objective: To determine whether low concentrations of ethanol can prevent and treat biofilms of Pseudomonas aeruginosa.

Methods: Ethanol was tested at a concentration range of 0.625–80% against laboratory and clinical isolates of P. aeruginosa for various time periods (2–48 hours). The following parameters were evaluated following ethanol exposure: prevention of biofilm formation, reduction of biofilm metabolic activity, and inhibition of biofilm regrowth.

Results: Exposing P. aeruginosa to twofold ethanol gradients demonstrated a significant biofilm inhibition at concentrations as low as 2.5%. Treating pre-formed biofilms of P. aeruginosa with 20% ethanol for 4 hours caused a sharp decay in the metabolic activity of both the laboratory and clinical P. aeruginosa isolates. In addition, treating mature biofilms with 20% ethanol prevented the regrowth of bacteria encased within it.

Conclusions: Low ethanol concentrations (2.5%) can prevent in vitro biofilm formation of P. aeruginosa. Treatment of previously formed biofilms can be achieved using 20% ethanol, thereby keeping the catheters intact and avoiding complications that can result from high ethanol concentrations.

Objectives: To assess our experience with perichondritis in a large group of patients hospitalized with this entity.

Methods: We retrospectively studied 114 patients who were admitted with perichondritis during 1987–2004, including their demographic details, medical history, current illness, etiology, pathogens and treatments. 

Results: The patients’ mean age was 41.8 ± 20.7 years. In more than half of the patients the etiology could not be determined. Forty-seven patients (41%) were treated prior to hospitalization for an average of 2.5 ± 1.9 days. Eight patients (7%) required surgical intervention. Pseudomonas aeruginosa was found to be the predominant organism (69% of available isolates) and was associated with a more advanced clinical presentation and longer hospitalization (P = 0.008). 

Conclusions:  Perichondritis develops in many cases after apparent minor trauma. Since P. aeruginosa is probably the predominant pathogen, initial treatment should include anti-pseudomonal antibiotics.

Background: Transmission of Pseudomonas aeruginosa among cystic fibrosis patients attending health camps has been reported previously.

Objectives: To determine the transmission of P. aeruginosa among CF[1] patients during three winter camps in the Dead Sea region in southern Israel.

Methods: Three consecutive CF patient groups were studied, each of which spent 3 weeks at the camp. The patients were segragated prior to camp attendance: patients who were not colonized with P. aeruginosa constituted the first group and colonized patients made up the two additional groups. Sputum cultures were obtained upon arrival, at mid-camp and on the last day. Environmental cultures were also obtained. Patients were separated during social activities and were requested to avoid social mingling. Isolates were analyzed by antibiotics susceptibility profile and by pulsed field gel electrophoresis.

Results: Ninety isolates from 19 patients produced 28 different fingerprint patterns by PFGE[2]. Isolates from two siblings and two patients from the same clinic displayed the same fingerprint pattern. These patients were already colonized with these organisms upon arrival. Two couples were formed during the camp, but PFGE showed no transmission of organisms. All other patients' isolates displayed unique fingerprint patterns and were distinguishable from those of other attendees, and none of the P. aeruginosa-negative patients acquired P. aeruginosa during camp attendance. Environmental cultures were negative for P. aeruginosa.

Conclusions: We were unable to demonstrate cross-infection of P. aeruginosa among CF patients participating in health camps at the Dead Sea who were meticulously segregated.