Drug abuse and hyperparathyroidism: a poisonous mixture in haemodialysis

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by Patrizia Scotto, MD
Operative Territorial Unit of Nephrology and Dialysis
Azienda USL N.8 - Cagliari - Italy

 


Introduction:

A 23-year-old male with chronic renal failure, due to unilateral renal agenesis with associated congenital contralateral upper urinary tract chronic obstructive nephropathy started haemodialysis in 1993. After four years on haemodialysis, he received a cadaveric renal allograft with triple immunosuppression consisting of cyclosporine, sirolimus and prednisone. The patient was discharged from hospital with serum creatinine levels averaging 1.8 mg/dL.
The renal graft function progressively deteriorated within twenty-two months after transplantation. (Figure 1)

Figure 1 - Evolution of the renal allograft function




Three biopsies were performed at 12, 17 and 20 months after transplantation to gain an insight into the progressive graft dysfunction. Thickening of the intima in the interlobar and pre-glomerular arteries was present in the first biopsy, while a pattern of chronic allograft nephropathy including tubular atrophy, interstitial fibrosis and glomerular lesions, was found at the third biopsy. (1).
On 2nd February 1999, bicarbonate hemodialysis was resumed on account of end-stage renal failure, using an arteriovenous fistula as hemoaccess.
Although he was treated with ACE inhibitors, Calcium channel blockers and Diuretics, the blood pressure was consistently above 145/90 and left ventricular hypertrophy (LVH) was detected by transthoracic echocardiography.
Severe hyperparathyroidism was diagnosed. Despite serum intact parathyroid hormone (iPTH) levels above 600 pg/mL, calcitriol was discontinuously undertaken because of hyperphosphatemia, largely due to poor dietetic and pharmacological compliance. (Tab.I)

In March 2000, parathyroidectomy was recommended on account of persistent serum levels of iPTH >1000 pg/mL associated with hyperphosphatemia. A scintigraphy with 99m Tc-sestamibi (MIBI) was performed; three parathyroid glands around the thyroid gland and a mediastinal ectopic parathyroid gland were detected. Even though the patient had been informed repeatedly and comprehensively about the necessity of parathyroidectomy (PTx), he refused over and over again.

TABLE I. Outcome of mineral metabolism and related therapy (Phase 1)




Dialysis, severe hyperparathyroidism and LVH were not his only problems. He often suffered from headaches, vomiting and loss of balance, which the patient correlated with his alcohol abuse. Changes of behaviour were also noticed: on Thursday and Saturday morning he was quite sleepy on dialysis, on Tuesday morning he was euphoric. In February 2000 on suspicion that alcohol was being used in conjunction with drugs, some samples of the outflow dialysate were collected in the early minutes of the dialysis to measure benzodiazepine, cannabis, cocaine and opiate levels. The tests repeatedly resulted positive for cocaine (2), whereas they occasionally resulted positive for heroin and cannabis too.
In October 2000, the patient complained of general fatigue, a dry cough, diarrhoea and fever accompanied by shivers and night sweats. Although physical examination was normal, some tests were performed and cefazidime was prescribed. (Tab. II)

TABLE II. Signs, symptoms and tests before his admission to hospital.





Question 1) - Which tests do you think are suitable for this patient?

a) Blood Cultures and Echocardiography
b) Echocardiography
c) Chest x-ray and Blood Cultures