Kallmann syndrome- type 1- X-linked
Overview
A rare inherited condition characterized by hypogonadism and impaired or absent sense of smell. The condition occurs as a result of failure of a part of the hypothalamus which results in hormonal imbalance. Type 1 is caused by a genetic defect located at chromosome Xp22.3.
Symptoms
* Reduced sense of smell * Absent sense of smell * Reduced hormone production by testes * Reduced hormone production by ovaries * Progressive loss of vision * Delayed puberty * Small genitalia * Delayed growth
Causes
* Nasal and sinus disease –Most common cause of anosmia –Allergic or vasomotor rhinitis and sinusitis result in temporary anosmia: Associated with chronic nasal congestion, rhinorrhea, postnasal drip, pale/boggy nasal mucosa, sinus swelling/tenderness, and headaches –Intranasal polyposis may occur, resulting in obstruction of nasal passages with temporary anosmia * Head/facial trauma –Second most common cause of anosmia –Permanent anosmia may result –CNS rhinorrhea may occur * Post-upper respiratory viral infection –Accounts for 20–30% of cases of anosmia * Iatrogenic –Amphetamines, certain antibiotics, nasal steroids, antithyroid agents, radiation * Poisoning –Chemical pollutants, heavy metals (lead), organic/inorganic compounds * Illicit drugs (e.g., intranasal cocaine) * CNS disorders (e.g., Alzheimer's disease, Parkinson's disease, anxiety disorders) * Neoplasms (e.g., nasal cavity, brain) * Endocrine disorders (e.g., diabetes mellitus, hypothyroidism, adrenal insufficiency) * Congenital disorders (e.g., Kallman's and Turner's syndromes) * Sjögren's syndrome * Vitamin deficiencies (e.g., vitamin B12, zinc)
Treatment
Temporary anosmia due to nasal and/or sinus disease is usually successfully treated medically –Systemic and/or intranasal corticosteroids –Antibiotics if coexisting bacterial infection –Antihistamines and avoidance measures if allergic component –Decongestants and/or saline lavage for nasal congestion –Polypectomy and sinus surgery if initial therapy is ineffective * No cure is available for permanent anosmia (e.g., due to postviral infections, trauma, congenital disorders); however, regeneration of neural elements may occur over a period of days to years * Anosmia due to CNS and endocrine diseases require treatment of the underlying illness * Vitamin supplementation in cases of vitamin deficiency