CASE REPORT

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A 45-year-old female presented with bilateral flank pain and renal insufficiency. History revealed bulimia for >20 years and abusive intake of diuretics. Clinically, no apparent abnormalities were detected. Serum-creatinine was 2.2 mg/dl (eGFR 26 ml/min/1.73m²), and urinary albumin-creatinine-ratio was 384 mg/g. Marked electrolyte disturbances were observed (K+ 2.7 [normal range: 3.5-5.3] mmol/l, Ca++ 2.72 [2.1-2.7] mmol/l, Mg+ 0.64 [0.7-1.0] mmol/l, Cl- 94 [95-110] mmol/l) as well as contraction alkalosis(pH 7.461, actual bicarbonate 29.1 [22.0-26.0] mmol/l).

Plain x-ray (figure 1) and conventional tomography (figure 2) showed multiple calcifications (arrows) up to 0.5 cm in diameter at the cortical-medullary zone. A diagnosis of nephrocalcinosis was made. Most likely, both, chronic hypokalemia induced by bulimia and abuse of furosemide and xipamide have caused nephrocalcinosis.

Following nearly one year of continuous ambulatory care in our nephrology ward, we were able to convince the patient to start behavioral and psycho-therapy. Meanwhile, the patient is highly motivated, and stopped vomiting and diuretics abuse. Renal function slightly improved (1.9 mg/dl; eGFR 28 ml/min/1.73m²). potassium increased to normal(4.5mmol/l) as did calcium (2.52 mmol/l) and alkalosis disappeared.

ACKNOWLEDGEMENT

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We wish to acknowledge the contribution of Harald Riedelsberger, MD, radiologist, who provided the radiographs.