Growth Without GH: A Case Series and Literature Review.

Linear growth is traditionally attributed to the growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis, yet "growth without GH" is documented. We report five patients with severe GH deficiency-one congenital and four acquired, who reached normal or tall stature despite persistently low IGF-1. All patients had obesity and metabolic complications (insulin resistance, dyslipidemia, and/or fatty liver). Catch-up or sustained growth occurred before or independent of sex-steroid replacement in most cases. One patient with lifelong hypogonadism showed slow, prolonged growth with delayed epiphyseal fusion. Three patients also received recombinant human GH (rhGH), without a significant impact on overall growth velocity, but with favorable metabolic outcomes. Findings support multifactorial drivers of linear growth beyond the GH/IGF-1 pathway. Likely contributors include insulin signaling associated with adiposity, permissive thyroid hormone action, local growth-plate paracrine pathways, and, in hypogonadism, delayed epiphyseal closure. Genetic modifiers that enhance chondrogenesis or delay growth-plate fusion may contribute. We also reviewed the published literature on "growth without GH," integrating single-case reports and series to contextualize these mechanisms and outcomes. In conclusion, profound GH deficiency does not preclude near-normal or accelerated growth. In "growth without GH," therapeutic priorities should pivot from stature to cardiometabolic risk reduction. rhGH may be considered to improve metabolism when individualized and closely monitored, recognizing that height velocity is often adequate. Notably, rhGH consistently improved lipid profiles and steatohepatitis in two patients, suggesting a primarily metabolic benefit. Lifelong follow-up from childhood into adulthood is essential.