Case report: Acromegaly or end-stage renal disease?

Abstract

Introduction: A 41 year old female patient with end-state renal disease (ESRD) caused by interstitial nephritis came to our outpatient clinic. A renal transplantation was planned soon. During the routine examination before transplantation, a slightly elevated IGF-I level was found. We were to clarify whether she had acromegaly. Medical history: Body size unchanged since puberty, shoe size increased 1 size during the last 10 years. No enlargement of hands, no sweating, no head pain, regular menses. Physical examination: 1.82m, 72kg, blood pressure 145/80mmHg, heart rate 59/min, lean fingers and tongue not swollen, thyroid slightly enlarged. Evaluation: At first visit: IGF-I 340µg/l (Immulite®, age- and gender-specific normal values 97–263µg/l), hGH 7.1µg/l (<5µg/l), IGF-BP3 5870µg/l (3500–6600µg/l), creatinine and urea elevated. Re-evaluation 5 weeks later: An oral glucose tolerance test was performed. No suppression of GH was seen (basal 3.4µg/l, nadir 1.7µg/l), but a paradoxical increase (11µg/l) after 60min. Corresponding IGF-I 273µg/l (97–263µg/l) was elevated again (IGF-BP3 5410µg/l (3500–6600µg/l)). We initiated a MRI of the sella region, which showed no pituitary adenoma. Blood samples were sent to another laboratory (DSL, Heidelberg) for reassessment in a different assay. The results showed elevated IGF-I and IGF-BP3 levels in both samples (717 and 677µg/l (101–303µg/l), 8117 and 8474µg/l (2080–4310µg/l)). Follow up: Renal transplantation was carried out 3 weeks later. 21 months later, a blood sample was taken again. Now GH (0.2µg/l), IGF-I (251µg/l) and IGF-BP3 levels (4140µg/l) were within the normal range.