Comparative yield of Salmonella typhi from blood and bone marrow cultures in patients with fever of unknown origin.

Over three years, a comparative study on 100 selected patients with fever of unknown origin was undertaken to determine the yield of Salmonella typhi from their blood and bone marrow cultures. The results indicate that in patients who had an infection with S typhi the organism was isolated from the bone marrow in all of them and from the blood in only 66%. This suggests that bone marrow cultures may be attempted when blood cultures are negative for bacterial growth after three to four days of incubation.

Eradication of a multiple drug resistant Salmonella paratyphi A causing meningitis with ciprofloxacin.

A previously healthy breast-fed baby was admitted at 10 days of age to a hospital in the north of Pakistan with diarrhoea and fever. He was treated for suspected sepsis with intravenous cefotaxime and tobramycin. Cultures of blood and faeces at that time proved negative. At 12 days of age, seizures began and examination of CSF revealed evidence of pyogenic meningitis but bacteria were neither seen microscopically nor isolated in culture. Ceftazidime was substituted for cefotaxime and carbenicillin was given also. Since the baby's condition continued to deteriorate with persistent fever, vomiting and recurrent seizures, he was transferred to the Aga Khan University Hospital, Karachi. Examination of CSF there confirmed the diagnosis of pyogenic meningitis and revealed Gram-negative bacteria. Cultures of CSF and faeces yielded Salmonella paratyphi A but the blood culture was negative. The isolate was found to be multiple antimicrobially resistant but sensitive to ciprofloxacin. Treatment with this drug was therefore started 3 days after the baby's admission to the Aga Khan Hospital. Within 36 h, improvement was observed. From then onwards, the baby made a progressive recovery and was healthy when seen at 7 months of age.

Cholera in children in Karachi from 1990 through 1995: a study of cases admitted to a tertiary care hospital.

Although cholera is an endemic disease in Bangladesh, India and other countries, it was never a significant cause of gastroenteritis in Pakistan before 1988. Since then, cases of cholera are identified each year, both in adults and children in Pakistan. In order to see the contribution of Vibrio cholerae as a cause of gastroenteritis in children, we reviewed the cases of cholera admitted in the pediatric ward of the Aga Khan University Hospital, Karachi, Pakistan. Of 4346 children hospitalized with gastroenteritis during 1990 through 1995, 348 children (8%) were confirmed to have cholera. The youngest child with cholera was seven days old. The mean age was 31 +/- 34 months. The cases of cholera were received from all over the city. Most cases were due to Vibrio cholerae Ogawa biotype ELTOR but the new strain, i.e., Vibrio cholerae 0139 was isolated in 14% cases in 1994. The sensitivity of Vibrio cholerae has also changed. In 1994, the organisms were resistant to commonly recommended antibiotics, i.e., tetracycline, ampicillin and erythrocin but sensitive to ceftrioxone, cefixime, ofloxacin and nalidixic acid. Adequate measures to improve hygiene and sanitation and supply of safe potable water is needed to prevent any future epidemic of cholera in the city.

Urinary tract infection.

Over two years, 9892 mid-stream urine samples from patients attending the Aga Khan University Hospital, Karachi were cultured. Significant bacterial growth was seen in 23.5% samples. Further identification of these organisms revealed 40% of E. coli, 16% Pseudomonas aeruginosa, 11% Klebsiella aerogenes, 5.0% Enterobacter sp., 13% Proteus sp., 4.0% Serratia liquifaciens, 1.0% Acinetobacter sp., 3.0% Citrobacter sp., 4.0% Enterococci, 0.5% Staphylococcus aureus. Results of sensitivity tests performed with antibiotics Ampicillin, Cotrimoxazole, Nitrofurantoin, Nalidixic acid, Gentamicin, Amikacin, Pipemedic acid, Cefotaxime, Azactam and Carbenicillin did not reveal any distinct pattern.

The spectrum of bacterial infections in febrile neutropenic patients: effect on empiric antibiotic therapy.

The aim of this retrospective analysis was to look at the spectrum of bacterial isolates and their resistance patterns to the commonly used antibiotics in the setting of febrile neutropenia. A total of 127 bacteria were isolated from patients with acute leukemias, lymphoproliferative disorders, aplastic anaemia and various solid tumours. Fifty-four percent organisms were gram negative; while the rest were gram positive. E. coli, pseudomonas aeruginosa, staphylococcus aureus, enterococcus and streptococci were the commonly isolated organisms. Forty-eight percent organisms were isolated from blood, 16% from urine, 13% from wounds and superficial abscesses and 11% from respiratory tract. E. coli exhibited a great degree of resistance to the commonly used antibiotics, such as pipericillin (70%), ofloxacin (50%) and aztreonam (50%). Pseudomonas and klebsiella also showed varying degree of resistance against the antibiotics. Staphylococcus aureus and staphylococcus epidermidis were almost universally resistant to penicillin and showed a variable degree of resistance to other antibiotics too. Compared to the previous reports, the pattern of bacterial isolates and their resistance to antibiotics has changed over the past years. Aminoglycosides and third generation cephalosporins seem to be the choice of antibiotics for the upfront management of febrile neutropenic patients.

Therapeutic implications of ofloxacin in the treatment of typhoid fever caused by multiply resistant Salmonella typhi.

The antibiotic of choice for the treatment of typhoid fever in most parts of the world is still chloramphenicol. Ampicillin and cotrimoxazole have been used in recent years. Selection of antimicrobials for therapy has been complicated by the emergence of Salmonella typhi strains resistant to the above mentioned antibiotics. Blood and/or bone marrow cultures of 30 adult patients grew S. typhi that was resistant to chloramphenicol, ampicillin and cotrimoxazole. However, these strains were sensitive to cefotaxime, ceftrioxone, aztreonam and ofloxacin. Ofloxacin 400 mg twice a day was given orally to these patients for 14 days. All patients recovered with no untoward side effect. We concluded that ofloxacin can be used as a drug of choice for typhoid fever, in those adult patients who are infected with S. typhi resistant to chloramphenicol, ampicillin and cotrimoxazole.

Bacteriuria and pregnancy outcome: a prospective hospital-based study in Pakistani women.

The prevalence of bacteriuria in Pakistani women and its association with complications of pregnancy was studied. Out of 1579 women, 77 had bacteriuria (4.8%). There was no association of age, gravidity, parity, haemoglobin, pre-eclampsia, mode of delivery, gestational age at delivery, preterm delivery and low birth-weight with presence of bacteriuria. With detection and treatment the pregnancy outcome of women with bacteriuria in pregnancy was the same as that of those without.

Therapy of multidrug resistant typhoid in 58 children.

Treatment of children with infections caused by Salmonella typhi strains resistant to the commonly used oral antimicrobials is a special problem. As children cannot be treated with quinolones, there is no form of oral therapy. Third generation cephalosporins, which have been shown to be effective against typhoid caused by ampicillin sensitive strains of S. typhi were effective against typhoid caused by ampicillin, chloramphenicol and sulfamethoxazole/trimethoprim-resistant strains. We treated 28 children with ceftriaxone and 8 with cefotaxime. We found ceftriaxone to be more effective than cefotaxime with significantly lower relapse rate. Antibiotic therapy of 19 other children, initially treated in a similar manner, was altered for ease of therapy or due to poor response to therapy. The high cost of this parenteral therapy and the problems in its delivery point to the need for safe, effective oral therapy.

Neonatal sepsis in Pakistan. Presentation and pathogens.

The case records of all neonates admitted to the neonatal unit at Aga Khan University Hospital (Karachi) in a 30 month period (Nov. 86-April 89) were analysed. Of 60 neonates with confirmed sepsis, 33 (55%) had non-nosocomial infection (NNC) whereas 27 (45%) had nosocomial sepsis (NC). The most common organisms causing early-onset NNC sepsis were Klebsiella species (53%) and Escherichia coli (10%), whereas the organisms causing late-onset NNC sepsis included Salmonella parathypi (21%), Group A Streptococcus (21%), Escherichia coli (14%) and Pseudomonas species (14%). Klebsiella was the most common organism causing NC sepsis, others being Staphylococcus aureus (15%) and Serratia species (15%). The mortality in NC sepsis, early-onset and late onset NNC sepsis was 44%, 26% and 43%, respectively. Risk factors associated with NNC sepsis included low birthweight, prematurity and prolonged and complicated deliveries. There was a high incidence of drug resistance to ampicillin and gentamicin among gram-negative organisms causing sepsis (mean 67%).

Multidrug-resistant typhoid in children: presentation and clinical features.

Typhoid accounts for 8% of pediatric admissions to the Aga Khan University Hospital in Karachi, Pakistan. Over a 4-year period (1986-1989), 355 children had typhoid documented by culture of blood or bone marrow. Strains of Salmonella, resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole accounted for 20% of these cases. Compared with children infected by drug-susceptible strains of Salmonella, children with multiresistant infection were generally sicker at presentation and were more likely to be assessed as appearing "toxic" (P less than .001), as having disseminated intravascular coagulation (P less than .01), and as exhibiting hepatomegaly (P less than .01). The mortality was 4.2% among children with multiresistant infection and 1.4% among those infected with strains susceptible to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole; the higher mortality in the former group was probably due to a longer duration of illness (P less than .05) and to ineffectual oral antimicrobial therapy before hospitalization.