The kidney in acromegaly: renal structure and function in patients with acromegaly during active disease and 1 year after disease remission

Abstract

Background: The GH/insulin-like growth factor 1 axis is physiologically involved in the regulation of electrolytes and water homeostasis by kidneys, and influences glomerular filtration and tubular re-absorption processes. The aim of the study was to investigate renal structure and function in acromegalic patients during active disease and disease remission. Patients: Thirty acromegalic patients (15 males and 15 females), aged 32-70 years, were enrolled for the study. Ten de novo patients had active disease, whereas 20 patients showed disease remission 1 year after medical treatment with somatostatin analogs (SA) (ten patients) or surgery (ten patients). Thirty healthy subjects matched for age, gender, and body surface area were enrolled as controls. Results: In both active (A) and controlled (C) patients, creatinine clearance (P!0.001) and citrate (P!0.05) and oxalate levels (P!0.001) were higher, whereas filtered Na (P!0.001) and K (P!0.001) fractional excretions were lower than those in the controls. Urinary Ca (P!0.001) and Ph (P!0.05) levels were significantly increased compared with the controls, and in patients with disease control, urinary Ca (P!0.001) levels were significantly reduced compared with active patients. Microalbuminuria was significantly increased in active patients (P!0.05) compared with controlled patients and healthy control subjects. The longitudinal (P!0.05) and transverse (P!0.05) diameters of kidneys were significantly higher than those in the controls. In all patients, the prevalence of micronephrolithiasis was higher than that in the controls (P!0.001), and was significantly correlated to disease duration (rZ0.871, P!0.001) and hydroxyproline values (rZ0.639, P!0.001). Conclusions:The results of the current study demonstrated that acromegaly affects both renal structure and function. The observed changes are not completely reversible after disease remission.

Long-term growth hormone treatment in short children with CKD does not accelerate decline of renal function: results from the KIGS registry and ESCAPE trial

“…In contrast, an increase in GFR, plasma flow and kidney size, glomerular hypertrophy and functional tubular disturbances have been reported in some but not all patients with acromegaly [19][20][21]. The conflicting findings from studies in experimental animals, acromegalic patients and short children on rhGH treatment, respectively, might be explained by the excessive magnitude of the GH production rate resulting in high GH levels in transgenic animals and acromegalic patients.…”

Prevalence of Simple Renal Cysts in Acromegaly

“…However, to the best of our knowledge, with the exception of size, there have been no reports describing the structural changes in the kidney in patients with acromegaly (19). In this study, we investigated the prevalence of renal cysts in patients with acromegaly.…”

Treatable glomerular hyperfiltration in patients with active acromegaly

“…Several reports have offered hypotheses on the mechanism of hyperfiltration induced by GH/IGF1 excess. Auriemma et al hypothesized that the increase in kidney size might lead to an increase in GFR, RPF, and tubular reabsorption, which may enhance renal filtration and reabsorption processes (20). Ikkos et al hypothesized that the increased GFR in acromegaly could be attributed to primary increases in extracellular fluid volume without any changes in the filtered fraction (8).…”