Microphallus early management in infancy saves adulthood sensual life: A ‎‎comprehensive review

Table 1 The causes of Microphallus and Micropenis

Factor		Description
Genetics	Specific genes mutations	Genes related to testosterone production and androgen receptor function. Genes associated with the genital tubercle development
	AIS
	Genetic deficiencies in Enzymes Involved in Hormone Production e.g., 5 alpha-reductase deficiency
	Genetic abnormalities affecting hormonal signalling
	Genetic disorders affecting pituitary gland function
	Genetic causes of congenital adrenal hyperplasia (deficiency in steroidogenic acute regulatory protein (STAR gene mutation), 3 beta-hydroxysteroid dehydrogenases (salt-wasting, non-salt-wasting, and non-classic types), 17 α-hydroxylase (mutations in the CYP17A1 gene located on chromosome 10q24-q25)
	Chromosomal Abnormalities e.g., Klinefelter syndrome (XXY), Trisomy of the chromosomes 8, 13, 18 or 21
	Inherited syndromes	Bardet-Biedl syndrome, Prader-Willi syndrome and Kallman syndrome (hypogonadotropic hypogonadism, osteoporosis, hearing impairment, and anosmia). Noonan syndrome (hypertelorism, short neck, low-set ears, skeletal malformation, bleeding disorders, and pulmonary valve stenosis). Others: Charge syndrome, Silver Russel syndrome, Rud syndrome
Hormonal and endocrinal causes	Primary Hypogonadism: Either congenital or acquired ‎ e.g., Anorchia, Klinefelter and poly-X syndromes, gonadal dysgenesis (incomplete form), luteinizing hormone receptor defect (incomplete form), testosterone steroidogenesis (incomplete form), Noonan syndrome, Trisomy 21, Robinow syndrome, Bardet-Biedl syndrome, Laurence-Moon syndrome
	Secondary Hypogonadism: Secondary to pituitary gland or hypothalamus disorders, resulting in decreased ‎secretion of luteinizing hormone and follicle-stimulating hormone ‎
	AIS
	Enzyme deficiencies affect testosterone synthesis or its conversion to the more ‎potent dihydrotestosterone
	Growth hormone deficiency or abnormalities in IGF-1 ‎
	Hypothyroidism
	Adrenal gland disorders ‎ such as adrenal hyperplasia
Anatomical and structural abnormalities	Penis agenesis, cloacal dystrophy, hypospadias or chordee, Peyronie's disease, corpus cavernosa and corpus spongiosum hypoplasia, vascular abnormalities, ligaments or connective tissue abnormalities, and inadequate penile shaft length
Environmental factors	Antenatal exposure	Endocrine-disrupting chemicals, including phthalates, bisphenol A, and ‎certain pesticides
		Anti-androgenic drugs
		Maternal substance abuse, including alcohol, drugs, or tobacco
		Ionizing radiation
		Antenatal infections
		Inadequate nutrition and a poor maternal diet ‎
		Pollutant exposure such as heavy metals and dioxins.
		Antenatal exposure of antifungal
	Postnatal exposure	Improper or excessive use of antibiotics or hormonal medications
		Hormonal treatments for conditions like precocious puberty or delayed puberty‎
		Surgical interventions or treatments for disorders affecting the genitalia ‎
Idiopathic	Unknown cause

AIS: Androgen Insensitivity Syndrome; STAR: Spliced transcripts alignment to a reference; CYP17A1: Cytochrome P450 17A1; IGF-1: Insulin-like growth factor-1.