Tehran University Medical Journal

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Background: Septic arthritis in neonates can be difficult to diagnose and may be associated with severe morbidity and even mortality. A majority of apparent septic arthritis cases may have a negative culture, thereby creating a dilemma regarding treatment. The present study investigates demographic, laboratory and clinical variables of septic arthritis in neonates hospitalized over a period of 17 years.
Methods: The medical files of all neonates hospitalized in Imam Khomeini and Vali-e-Asr Hospitals in Tehran, Iran, from 1989 to 2005 were assessed and the files of 59 neonates with a diagnosis of septic arthritis were further evaluated. Variables such as age, sex, gestational age, birth weight, history of hospitalization, body temperature, involved joints, blood and joint fluid cultures, ESR, CRP, and WBC count were evaluated in this group of hospitalized patients. Results: Of the 59 neonates, 39 cases were male and 20 cases were female. At the time of hospitalization, 45.8% of the neonates were 20-28 days old and 52.2% were 10-20 days old, and 67.7% and 35.6% of cases had been preterm and had low birth weight, respectively. Histories of hospital admission were found for 30.5% of patients. The two most common joints involved were hip (30.5%) and knee (23.72%). The mean body temperature was 36.6oC. ESR was elevated in all patients (mean 85 mm/h) and CRP was positive in all cases. The WBC count was >15,000/mm3 in 39% of the neonates and was in the range of 10,000-15,000/mm3 for 47.4%. Blood and joint fluid cultures were positive in 51% and 91.5% of cases, respectively. The organisms isolated from joint fluid culture were Klebsiella (54%), S. aureus (37%) and E. coli (9%). Conclusion: Due to the rarity of septic arthritis in neonates and paucity of signs and symptoms, all neonates with a high index of suspicion should be examined carefully with septic arthritis in mind.

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Background: Bacterial pneumonia is one of the most common causes of morbidity and mortality, and accurate diagnosis and treatment of the pneumonia causative agent, especially in polybacterial cases, is difficult and much appreciated. The aim of this study was to determine the causative agents and antimicrobial susceptibility of polybacterial pneumonia in patients with lower respiratory tract infections.Methods: In this retrospective cross-sectional study, 167 cases with symptoms of lower respiratory tract infection (LRTI), admitted since March 2010 to March 2013 to Baqiyatallah Hospital, Tehran, were studied. Bronchoalveolar lavage (BAL) samples have been obtained from all these patients and have been investigated for the presence of bacterial causative agent, presence of polybacterial pattern of the infection, and the pattern of antimicrobial susceptibility testing by disc diffusion method. Also, the samples have been studied for the presence of Mycobacterium tuberculosis through culture of specific media, separately.Results: From 167 patients (62 women and 105 men), 90 cases were positive for the presence of bacterial pathogens while 77 cases were negative by culture. The incidence of bacterial pneumonia was not statistically different between men and women. Totally 117 bacterial isolates were obtained belonging to 15 different bacterial species. Mycobacterium tuberculosis (25%), Pseudomonas aeruginosa (15%) and Staphylococcus aureus (14%) were the most frequent pathogens identified. 72 percent of pneumonic cases were monobacterial infections and the others were polybacterial infections (23% two-bacterial, and 5% three-bacteria). The highest antibiotic resistance rate was seen for amoxicillin and the lowest one was seen for vancomycin.Conclusion: This study found that the prevalence of bacterial pneumonia increases with age, and also is caused by different etiologic agents. A high percentage of negative cases may be due to fastidious bacteria, viral agents, and previous antibiotic therapy. Due to high levels of resistance to antimicrobial agents, accurate diagnosis and susceptibility testing of pneumonic patients is essential.