Tubular dysfunction and acute tubulo-interstitial
nephritis (AIN) have been described secondary to drugs, toxins as well
as infections(1). Salmonellosis has been associated with immune
glomerulonephritis, bacteremia or pyelonephritis(2). AIN secondary to
salmonella typhimurium has been reported in a 12-year-old girl(3)
and adults(4,5) either in isolation or with schistosomiasis.
We describe a child with acute tubular dysfunction
after an infection with Salmonella enteritidis.
Case Report
A 13-year-old boy presented with diarrhea and
vomiting of 3 days duration associated with fever and generalized
malaise. There was no history of drug ingestion or of travel abroad.
He was well grown (height 75th centile, weight 50th
centile), but severely dehydrated with a poor capillary refill and cold
peripheries. His blood pressure was normal (114/60 mm of Hg) with no
other systemic abnormality.
Urine examination revealed a specific gravity of
1.010, 1+ blood and 1+ protein with no glucose. Microscopy revealed
scanty red cells and no eosinophils. His hemoglobin was 19.1 g/dL with a
normal red cell morphology. Plasma sodium was 125 mmol/L, potassium 2.8
mmol/L, urea 58 mmol/L, chloride 78 mmol/L, bicarbonate 32 mmol/L and
creatinine 425 micromoles/L. The plasma phosphate was high at
presentation (4.4 mmol/L) but on rehydration, dropped to 0.6 mmol/L. The
plasma calcium, alkaline phosphatase and liver function tests remained
normal. The fractional excretion of sodium was 2% and tubular phosphate
reabsorption was 56% (normal >80%). Urinary chloride was normal with no
aminoaciduria or glucosuria. Urine osmolality at presentation was 400
mOsm/kg. the daily urine output remained high at 2.5 litres. Mycoplasma
titres were negative. Ophthalmic review was also normal. An abdominal
ultrasound revealed enlarged kidneys.
Blood and stool cultures revealed Salmonella
enteritidis (09, G phage type 6) but the urine culture was negative. He
was rehydrated and treated with Ciprofloxacin for a week. The fever
subsided in 48 hours while the diarrhea persisted for 5 days.
Proteinuria and haematuria disappeared and the renal function settled to
normal within 5 days (plasma creatinine 0.97 micromoles/L). He needed
oral phosphate supplements for 3 weeks.
Presence of hyposthenuria, proteinuria, hematuria,
phosphate loss in the urine and dehydration out of proportion with
gastro-intestinal symptoms, indicating polyuria suggested acute tubular
dysfunction in asso-ciation with Salmonella enteritidis. A negative
urine culture ruled out pyelonephritis. As the renal function improved
rapidly, a kidney biopsy was not performed. Hence, TIN could not be
ascertained.
Contributors: PVD was involved in clinical
management, data acquisition, interpretation and draft of the article;
RDG carried out critical revision and interpretation.
Funding: None.
Competing interests: None stated.
