Indian Pediatrics 2003; 40:252-254 

Pleural Effusion in Complicated Salmonella Paratyphi A Infection

Enteric fever can present with unusual manifestations. We observed a rare case of Salmonella paratyphi A infection in which multiple organs were involved and the organism was isolated from pleural fluid and blood. In the present era of antimicrobial drug resistance, awareness about such atypical presentations is essential to initiate a prompt treatment.

Key words: Pleural effusion, S. paratyphi.

Enteric fever continues to be a global health problem, with an estimated 13-17 million cases worldwide resulting in ~600,00 deaths per year(1). Paratyphoid fever caused by Salmonella paratyphi A is less serious than typhoid fever(2,3). Consequently, severe complications are uncommon. We present an unusual case of enteric fever caused by S. paratyphi A in which multiple organs were involved in an immunocompetent child and the organism was isolated from pleural fluid.

Case Report

A 2½ year-old-boy presented with history of abdominal pain and loose stools for one month, fever with chills and rigors for one week, oliguria and swelling in the legs with passage of high coloured urine for two days. Physical examination revealed a febrile child with temperature of 39ºC. There was pallor, mild icterus and pedal edema. Anthro-pometric parameters were appropriate for age (weight 12.5 kg, height 88 cms). The respiratory rate was 28 per minute; breath sounds were diminished over the left lower lobe, without any evidence of rhonchi or crepitations. The liver was enlarged 3 cm below right costal margin and spleen 1 cm below left costal margin.

Initial investigations showed hemoglobin level of 8 g/dL, total leucocyte count 7000/mm3 (20% neutrophils, 80% lymphocytes) and adequate number of platelets. Blood chemistry done after 48 hours of hospital-ization showed asparate aminotrans-ferase level of 176 IU/L, alanine amino-transferase 117 IU/L, alkaline phosphatase 544 IU/L, total bilirubin 0.6 mg/dL, direct bilirubin 0.3 mg/dL, total proteins 6.1 g/dL, albumin 3.6 g/dL, urea nitrogen 18 mg/dL, creatinine 0.5 mg/dL, sodium 137 mEq/L and potassium 4.1 mEq/L.

The urine output at admission was 0.6 ml/kg/hour. Urinalysis showed traces to 1+ protein, no red cells, 2-3 epithelial cells and 10-15 white blood cells per HPF. No bacteria were seen. Microscopic examination of stool was normal. Viral markers for hepatitis A, B and C were negative. Ultrasonography of abdomen revealed a subpulmonic effusion on left side. Rest of abdomen including liver, gall bladder, spleen and kidney were within normal limits. Two samples each of blood, urine and stool were sent for culture. A small amount of pleural fluid, aspirated on two consecutie days, was also sent for culture and a serum sample sent for serological diagnosis of enteric fever. Cultures of urine were sterile and no pathogen was isolated from stool culture. However, both the samples of blood and pleural fluid grew S. paratyphi A, which was sensitive to ciprofloxacin and ceftriaxone but resistant to nalidixic acid, amoxicillin, cotrimoxazole and chloramphenicol by the standard NCCLS method. The MIC of ciprofloxacin was 0.19 µg/mL by E-test (AB Biodisk, Solne, Sweden). The titre of Somatic (0) and flagellar (H) antibodies for S. paratyphia A was >320.

The child was treated with cefotaxime and cloxacillin initially. Once culture report was available the treatment was changed to ceftriaxone and cloxacillin was stopped. After one week of therapy, the pleural effusion resolved and the patient was afebrile. He was discharged after two weeks treatment with ceftriaxone.

Discussion

Enteric fever encompasses a disease with a range of severity, with typhoid fever being severe and paratyphoid fever a milder illness. Worldwide, it accounts for 16 million cases annually with an estimated 600,00 deaths(4). The disease is endemic in India with more than 3 lakh cases of enteric fever occurring each year(5). S. typhi accounts for the majority of infections. S. paratyphi A is less common but has shown a rising trend over the past five years whereas S. paratyphi B is rare(6). In a study done at a low income community of Delhi, the incidence of typhoid fever was 27.3/1000 person years in children under 5 years of age, 11.7 at 5-19 years and 1.1 between 19-40 years(7).

In typhoid, involvement of liver is a consistent feature(3,8). The other common complications include relapse, perforation and hemorrhage from bowel ulcerations(3). However, such complications are extremely rare in paratyphoid fever. The present patient had fever and loose-motions since one month for which he was treated empirically. He subsequently developed oliguria and pleural effusion. Pleural effusion due to Salmonella spp. in immunocompetent children has been rarely reported. A MEDLINE search done on this subject revealed only one report of a case of empyema in an HIV positive, immuno-compromised patient, from which S. paratyphi was recovered(9). However, our patient was otherwise immunocompetent. Another recent report documented a case of pleural empyema due to group B Salmonella in an immunocompetent child with diarrhea(10).

An appropriate antibiotic is essential for the treatment of patients with typhoid fever. The recent emergence in developing countries of Salmonella strains with multiresistance has caused major problems. In recent years, ciprofloxacin has emerged as a highly effective agent in the treatment of enteric fever, thus therapeutic failure to quinolones is an important trend of concern(1,11). Recently, nalidixic acid resistant Salmonella strains have also been reported. Thus, all strains of Salmonella must be screened for resistance to nalidixic acid and other quinolones. Subjects infected with nalidixic acid resistant strains require longer courses and prolonged doses of quinolones, or treatment with other antibiotics to which the strains are sensitive(1). The strain in this report was also resistant to nalidixic acid. This is unusual since nalidixic acid resistance in S. paratyphi has rarely been reported. The present regimen for treatment of enteric fever at our hospital comprises of ciprofloxacin or cefixime as first line drugs and ceftriaxone for patients who fail to respond to first line drugs. This patient was successfully treated with ceftriaxone to which the isolate was sensitive.

The clinical presentation of enteric fever can be confusing. Our patient had mild icterus. The viral markers for hepatitis viruses were negative, the transaminases were elevated but bilirubin was normal. This may be because the blood chemistry was done after 48 hours of hospitalization.

The present report emphasizes the rising incidence of complicated and multiresistant enteric fever in developing countries. Prompt recognition together with specific antimicrobial treatment can result in complete recovery of such patients. With the rapid increase in international travel, clinicians world over should keep enteric fever as one of the differential diagnosis in patients with prolonged and complicated fever.

Contributors: PM compiled the data and prepared the manuscript. R was involved with the micro-biologic work-up. LS was the clinician incharge.

Funding: None.

Competing interests: None stated.

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