Clarithromycin-induced granulomatous tubulointerstitial nephritis

Granulomatous Interstitial Nephritis - A Series of Six Cases

Granulomatous interstitial nephritis is an uncommon variant accounting for about 6% of all tubulointerstitial nephritis. The etiology can be drugs such as antibiotics and nonsteroidal anti-inflammatory drugs and infections such as tuberculosis, sarcoidosis, and fungal infections. Renal biopsy remains the gold standard for establishing the diagnosis. Here, we present a series of six cases of granulomatous interstitial nephritis, of which two cases were associated with lupus nephritis and another two cases with crescentic glomerulonephritis. Focal segmental glomerulosclerosis and mesangiosclerosis with chronic tubulointerstitial nephritis were detected in the rest of the cases. Most of the patients presented with features of nephrotic syndrome. Urine analysis showed albuminuria in all cases. In renal biopsy, interstitial epithelioid cell granuloma was a constant feature along with which there were foci of necrosis and moderate fibrosis in few cases. But none of our cases had any relevant history of prolonged drug intake. Tuberculosis and fungal infections were also ruled out. Thereby in this case series, we subgroup all the cases into two category four cases associated with granulomatous nephritis and two cases with idiopathic granulomatous nephritis.

Etiological diagnosis of granulomatous tubulointerstitial nephritis in the tropics

BACKGROUND

Granulomatous tubulointerstitial nephritis (GIN) is common due to infections, drugs or sarcoidosis. However, the cause is often difficult to establish and the studies are limited. We studied the etiology of GIN and compared the clinical and histological features and outcome in different etiologies at a tertiary care center in North India.

METHODS

Renaö biopsies from GIN cases diagnosed from January 2004 to April 2014 were retrieved. Stain for acid fast bacilli was performed in all biopsies. Etiological diagnosis was based on clinical features, extra-renal manifestations, radiology, history of drug intake and demonstration of infective agent. Tissue PCR for tubercular DNA was performed in seven biopsies.

RESULTS

Seventeen GIN patients [mean age 35 ± 15 years; males 11] were identified. Tuberculosis was the commonest etiology followed by idiopathic, sarcoidosis and fungal. Both tuberculosis and sarcoidosis patients presented with subnephrotic proteinuria and raised serum creatinine. Acid fast bacilli were demonstrated in 1/9 and necrosis was demonstrated in 3/9 granulomas in tuberculosis. Tissue PCR for tubercular DNA was positive in six TB patients and negative in one sarcoidosis patient. Patients responded well to appropriate therapy.

CONCLUSION

Etiological diagnosis of GIN is essential for timely and appropriate therapy. Tuberculosis is the commonest etiology (53%) in the tropics. Necrosis in granuloma, demonstration of acid fast bacilli, blood interferon gamma release assay and urine culture is not sensitive for the diagnosis of tuberculosis in GIN. Our findings suggest that tissue PCR for tuberculosis performed in an appropriate clinical setting is useful in the diagnostic evaluation of GIN.

Granulomatous tubulointerstitial nephritis secondary to omeprazole

Drug-induced interstitial nephritis is a common cause of acute kidney injury indicated by elevated serum creatinine. We report a case of omeprazole-induced acute granulomatous interstitial nephritis (GIN). Our patient developed acute GIN secondary to omeprazole ingestion requiring haemodialysis. Treatment with steroids and withdrawal of omperazole was successful allowing the patient to discontinue haemodialysis in 3 months. She remains dialysis free with chronic kidney disease stage IV, reflected by a serum creatine of 191 μmol/L and estimated glomerular filtration rate of 23 mL/min/1.73 m(2) at 5 years on follow-up.

Unusual manifestations of acute Q fever: autoimmune hemolytic anemia and tubulointerstitial nephritis

Q fever is a worldwide zoonotic infection that caused by Coxiella burnetii, a strict intracellular bacterium. It may be manifested by some of the autoimmune events and is classified into acute and chronic forms. The most frequent clinical manifestation of acute form is a self-limited febrile illness which is associated with severe headache, muscle ache, arthralgia and cough. Meningoencephalitis, thyroiditis, pericarditis, myocarditis, mesenteric lymphadenopathy, hemolytic anemia, and nephritis are rare manifestations. Here we present a case of acute Q fever together with Coombs’ positive autoimmune hemolytic anemia (AIHA) and tubulointerstitial nephritis treated with chlarithromycin, steroids and hemodialysis. Clinicians should be aware of such rare manifestations of the disease.

Clarithromycin-induced acute interstitial nephritis and minimal change disease

Drug associated acute interstitial nephritis and minimal change disease has been well documented but the simultaneous presentation of both is rare and has not been reported with clarithromycin. We describe a case of simultaneous acute tubulointerstitial nephritis and minimal change disease induced by clarithromycin. The patient had acute kidney injury, nephrotic syndrome, eosinophilic pneumonitis and a maculopapular skin rash. The role of steroid therapy in acute interstitial nephritis is controversial but is accepted as beneficial in minimal change nephrotic syndrome. Steroid therapy in our patient resulted in complete clinical resolution.