Salmonella typhimurium (STM) is a non-typhoid salmonella which essentially entails intestinal infections. Extra-intestinal involvements such as septicaemia or renal lesions are uncommon in developed countries and mainly occur in frail people [1]. We describe a case of STM septicaemia with acute nephropathy in an elderly subject.
A 92-year-old man was hospitalized for epigastralgia; vomiting and fever of 40°C suddenly appeared. His medical history consisted of non insulin-dependent diabetes, deep-vein thrombosis, chronic respiratory insufficiency, mild chronic renal insufficiency, a pacemaker and chronic alcoholism. He had been treated by omeprazole, fluindione, furosemide, gliclazide, molsidomine, trinitrine, ramipril, trimetazidine and sertraline. Except for a mild abdominal pain without contracture, the physical examination was normal and blood pressure was 110/80 mmHg. Initial biological screening showed moderate hyperleukocytosis, macrocytosis without anaemia, inflammatory syndrome [C-reactive protein (CRP) 98 mg/l, fibrinogen 5.5 g/l], renal insufficiency (serum creatinine 160 µmol/l, urea 16 mmol/l) and an increase of -glutamyltransferase (210 IU/l). A few hours after admission, profuse diarrhoea, dyspnoea and haemodynamic shock appeared. The second set of laboratory tests disclosed lactic acidosis [pH 7.10, moderate decrease of pCO2 to 33 mmHg (normal: 3545), reduction of serum bicarbonate to 15 mmol/l (normal: 2230) and increase of serum lactate to 523 mg/l (normal: 63189)], an increase of CRP to 198 mg/l, mild anaemia and aggravation of renal insufficiency (creatinine 429 µmol/l, urea 25 mmol/l). Serum total protein and albumin were in the normal range. Complement was normal. Urinalysis showed proteinuria 2.83 g/l, haematuria 6 x 106 red blood cells/ml without leukocytes or bacteria. The patient's daily urine output was
1.52.5 l. Blood and fecal cultures showed the same STM, but urinary culture was sterile. Abdominal ultrasonography showed normal morphology and height of the kidneys and urinary tract. The patient was treated with two antibiotics (ceftriaxone and ciprofloxacine), perfusion of macromolecular and sodium bicarbonate solutions, insulin, oxygen, an antypiretic and an antiemetic. Molsidomine and trinitrine were stopped. A few days later, clinical examination became normal and biological analysis revealed anterior values of creatinine and urea and disappearance of proteunuria and haematuria.
Septicaemia or extra-digestive involvements are exceptional in cases of STM infection. Immunosuppression, cancer, haemoglobinopathy, hepatic cirrhosis, gastric hypochlorhydria, past history of digestive surgery, malnutrition, previous antibiotic or antidiarrhoeic treatment, and extreme age contribute to its development [1]. Thus, in our case report the patient had risk factors because he was very old and possibly immunosuppressed owing to chronic alcoholism. Renal lesions which can be observed in the presence of STM infection are: abscess, acute pyelonephritis, tubulointerstitial nephritis, interstitial nephritis and glomerulonephritis [2,3]. In our report, pyelonephritis was excluded because urinary analysis and culture carried out before antibiotics were initiated did not reveal any infection. However, there were arguments for tubulointerstitial/interstitial nephritis and for glomerulonephritis in addition to haematuria and renal insufficiency found in the previous two cases. Therefore, the normality of complement and the very quick decrease of renal signs with the treatment of infection argue for acute tubulointerstitial/interstitial nephritis, whereas the absence of leukocytosis in urinalysis and the high rate of proteinuria, 3 g/l, are noted in glomerulonephritis. However, proteunuria can be important in cases of tubulointerstitial/interstitial nephritis [4]. Only histopathological analysis of renal biopsy showing typical changes for tubulointerstitial/interstitial nephritis or for glomerulonephritis confirms the diagnosis [5,6]. Renal biopsy was not performed in this case because of its potential complications and the patient's renal function tests spontaneously improved with antibiotic and symptomatic treatments of the infection.
To conclude, this report adds further information relating to rare cases of acute nephropathies due to STM infection published in the literature and should prompt the physician to consider it, particularly when renal signs are associated with intestinal symptoms, in order to make a suitable analysis and begin an appropriate treatment quickly.
Conflict of interest statement. None declared.
University Hospital Geriatrics Dijon France Email: patrick.manckoundia{at}chu-dijon.fr
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