Treatable glomerular hyperfiltration in patients with active acromegaly

A cohort study found a high risk of end-stage kidney disease associated with acromegaly

Acromegaly is a chronic systemic disease caused by excess levels of growth hormone and insulin-like growth factor-1 and is associated with numerous complications. Significantly, there is a lack of longitudinal data on kidney complications in patients with acromegaly. As such, we investigated the risk of end-stage kidney disease (ESKD) (stage 5D, 5T) in these patients with nationwide data obtained from the National Health Information Database of the National Health Insurance Service in Republic of Korea. A retrospective cohort study was conducted of 2.187 patients with acromegaly and 10,935 age- and sex-matched (1:5) control subjects without acromegaly over a mean follow-up period of 6.51 years. The study outcomes were analyzed using Cox proportional hazards regression analysis controlling for age, sex, household income, residential area, type 2 diabetes, hypertension, dyslipidemia, urolithiasis, congestive heart failure, myocardial infarction, stroke, and atrial fibrillation. The incidence (per 1,000 person-years) ESKD was 2.00 among patients with acromegaly but only 0.46 among controls, (hazard ratio 4.35 (95% confidence interval 2.63-7.20)) implicating a significantly higher risk. After adjustment for covariates, the risk of ESKD (2.36 (1.36-4.12)) was still significantly higher in patients with acromegaly than that in controls. Among the covariates, diabetes and hypertension were significant facilitators between acromegaly and ESKD in mediation analysis. Pituitary surgery and somatostatin analogues did not significantly change these associations. Thus, acromegaly may be linked with a higher risk for ESKD both independently and through mediators such as diabetes and hypertension.

Renal effects of growth hormone in health and in kidney disease

Growth hormone (GH) and its mediator insulin-like growth factor-1 (IGF-1) have manifold effects on the kidneys. GH and IGF receptors are abundantly expressed in the kidney, including the glomerular and tubular cells. GH can act either directly on the kidneys or via circulating or paracrine-synthesized IGF-1. The GH/IGF-1 system regulates glomerular hemodynamics, renal gluconeogenesis, tubular sodium and water, phosphate, and calcium handling, as well as renal synthesis of 1,25 (OH)2 vitamin D3 and the antiaging hormone Klotho. The latter also acts as a coreceptor of the phosphaturic hormone fibroblast-growth factor 23 in the proximal tubule. Recombinant human GH (rhGH) is widely used in the treatment of short stature in children, including those with chronic kidney disease (CKD). Animal studies and observations in acromegalic patients demonstrate that GH-excess can have deleterious effects on kidney health, including glomerular hyperfiltration, renal hypertrophy, and glomerulosclerosis. In addition, elevated GH in patients with poorly controlled type 1 diabetes mellitus was thought to induce podocyte injury and thereby contribute to the development of diabetic nephropathy. This manuscript gives an overview of the physiological actions of GH/IGF-1 on the kidneys and the multiple alterations of the GH/IGF-1 system and its consequences in patients with acromegaly, CKD, nephrotic syndrome, and type 1 diabetes mellitus. Finally, the impact of short- and long-term treatment with rhGH/rhIGF-1 on kidney function in patients with kidney diseases will be discussed.

Delayed diagnosis of acromegaly in a patient with focal segmental Glomerulosclerosis: a rare case report and literature review

BACKGROUND

Experimental studies have demonstrated that hypersecretion of growth hormone (GH) is associated with development of glomerular sclerosis. However, clinical case of such condition is very rare. Here we presented a case of focal segmental glomerulosclerosis (FSGS) associated with acromegaly.

CASE PRESENTATION

A 63-year-old man was diagnosed as nephrotic syndrome with minimal change disease for 2 years. Prednisone 1 mg/kg/day for 9 months led to no response. After admission, the second kidney biopsy indicated FSGS (NOS variant). On admission, his acromegalic features were noticed and he complained with a 20-year history of soft tissue swelling of hands and feet. Serum GH and insulin-like growth factor 1 (IGF-1) concentrations were both elevated significantly. An oral glucose tolerance test showed inadequate suppression of serum GH. The presence of a pituitary macroadenoma with a diameter of 1.4 cm by MRI confirmed the diagnosis of acromegaly. Then, the tumor was subtotally removed by trans-sphenoidal surgery. Partial remission of proteinuria was achieved 3 months after surgery and maintained during follow-up, with gradual reduce of corticosteroid.

CONCLUSIONS

This rare case suggested that the hypersecretion of GH may participate, at least in part, in FSGS development and progression. Early diagnosis and treatment of acromegaly is beneficial.

Transsphenoidal Surgery for Elderly Patients with Acromegaly and Its Outcomes: Comparison with Younger Patients

BACKGROUND

Elderly patients with acromegaly who have comorbidities may increasingly encounter perioperative complications; however, little data are available on the risks and outcomes of surgical treatment in these patients. We aimed to analyze and compare the results of transnasal transsphenoidal surgery (TTS) in elderly and younger patients.

METHODS

Eighty-seven consecutive patients with acromegaly who underwent TTS were included. We divided the patients into elderly (≥65 years) and younger (<65 years) groups and compared clinical characteristics, anesthesia risk, and surgical outcomes in these 2 groups.

RESULTS

The 87 patients included 24 (27.6%) in the elderly group and 63 (73.4%) in the younger group. Preoperative endocrinologic and radiologic assessments showed no significant differences between the 2 groups. Although a grade 3 American Society of Anesthesiologists Physical Status classification was more common in the elderly group (75% vs. 3%; P = 0.00001) owing to the severity of associated diseases, no significant between-group difference in perioperative complications was seen (17% vs. 6%; P = 0.142). Sixteen elderly patients and 45 younger patients achieved endocrinologic remission following surgery (67% vs. 71%; P = 0.426). The incidence rate of postoperative new pituitary deficit was similar in the elderly and younger groups (4% vs. 3%; P = 0.625). Approximately one-third of the elderly patients with diagnosed hypertension or diabetes mellitus tapered their medication after successful tumor removal.

CONCLUSIONS

TTS can be considered a safe treatment for both younger and elderly patients with acromegaly. Successful tumor removal provided a significant improvement in comorbidities even in elderly patients with acromegaly.