Clinical Studies in an Adult Male Patient with “Isolated Follicle Stimulating Hormone (FSH) Deficiency”

Abstract

Previous reports concerning isolated follicle stimulating hormone (FSH) deficiency and its possible pathogenesis have been conflicting. Both "normal" and "abnormal" FSH response to luteinizing hormone releasing hormone (LHRH) infusion have been described. We studied a 22-year-old man with normal basal serum testosterone and luteinizing hormone (LH) levels but undetectable levels of serum FSH. His serum LH titers showed one secretory spike during a 40-hour sampling at 20-minute intervals, whereas his serum FSH titers remained undetectable (less than 0.4 IU/l). Infusion of LHRH, 0.2 microgram/minute for 4 hours, induced the expected rise in the serum LH levels, but serum FSH levels remained low and only at one point reached 0.9 IU/l (normal adult male basal range 0.9-10.3 IU/l). The patient received LHRH, 100 micrograms/day, for three days. A second LHRH infusion, 0.2 microgram/minute for 4 hours, induced a normal rise in both the serum LH and FSH titers. The serum sex steroid binding globulin level was 10.3 ng DHT bound/ml (normal adult male level 8.0 +/- 0.3 ng DHT bound/ml). Presence of circulating auto-antibodies to the serum FSH was excluded by determining the binding of [125I] FSH with the patient's serum and comparing it with sera obtained from two normal male adult volunteers. Pituitary function tests were otherwise intact. Presence of a pituitary tumor was excluded by computerized axial tomography and x-ray studies of the pituitary fossa and normal visual fields. Clinically, the patient demonstrated cryptorchidism, hypospadias, surgically repaired omphalocele, and bilateral hearing loss.(ABSTRACT TRUNCATED AT 250 WORDS)

Mutations of follicle-stimulating hormone and its receptor: effects on gonadal function

“…In accordance with the most recent case reported, isolated FSH deficiency has previously been reported in men with variable degrees of oligoasthenoteratozoospermia, and normal testosterone production and virilization (18)(19)(20)(21)(22)(23), although FSH deficiency with normal fertility has also been reported (19,20). Hence, these reports have not clarified the contentious question about the role of FSH in adult testicular function.…”

“…In addition, there are several earlier reports on isolated FSH deficiency in men and women, but their genetic analysis was not possible at the time of most of these reports (18)(19)(20)(21)(22)(23)(24). In one patient, FSH deficiency was reported to be due to circulating antibodies to this hormone (25).…”

Reproductive ecology and life history of the human male

“…Subsequent readministration of GnRH revealed increased pituitary and gonadal responsiveness through maintenance of phase B gonadotropin and testosterone levels with markedly lower dosages of GnRH stimulation (redrawn from . its receptor exhibit variation in both structure and function in humans and other mammals (Layman et al, 1997a;Mozaffarian et al, 1983). Contrary to expectations, men with FSH gene mutations that result in severe transcription errors in the FSH molecule exhibit significant spermatogenesis and limited fecundity (Lindstedt et al, 1998;Phillip et al, 1998;Tapanainen et al, 1997), as do men with missense mutations in the FSH receptor gene (Gromoll et al, 1996;Simoni et al, 1999;Tapanainen et al, 1997).…”

Mutations of Gonadotropins and Gonadotropin Receptors: Elucidating the Physiology and Pathophysiology of Pituitary-Gonadal Function

“…These studies were done at the time when genetic diagnostics was not yet available. Some of the subjects with "isolated FSH deficiency" had associated disorders, such as cryptorchidism, hypospadias, omphalocele, deafness, the olfactory-genital dysplasia syndrome, chromosomal alterations, autoimmunity, or short stature (160,(165)(166)(167)(168), and therefore such patients may not be representative of truly isolated FSH deficiency. However, many of them seem to fulfill the diagnostic criteria.…”