A low serum free T4 level with a low, or normal serum TSH level would indicate secondary hypothyroidism. A normal TSH response to TRH is a rise at 20 minutes post-dose and then a fall by 60 minutes, while a normal prolactin response would be a rise at 20 minutes and then a fall by 60 minutes. A continued rise of TSH at 60 minutes implies hypothalamic damage. Secondary hypothyroidism is indicated by a low baseline TSH level, while primary hypothyroidism is demonstrated by a raised TSH.

Classic Kallmann syndrome (KS) is due to isolated hypogonadotropic hypogonadism. Most patients have gonadotropin-releasing hormone (GnRH) deficiency, as suggested by their response to pulsatile GnRH therapy. The hypothalamic-pituitary function is otherwise normal in most patients, and hypothalamic-pituitary imaging reveals no space-occupying lesions. By definition, either anosmia or severe hyposmia is present in patients with Kallmann syndrome.

McCune–Albright syndrome, characterised by polyostotic fibrous dysplasia, café au lait spots, sexual precocity, and hyperfunction of multiple endocrine glands, is the result of G-protein abnormality.

Based on the clinical scenario, the boy is going through normal pubertal changes.In the 3 years before puberty, low pulsatile LH levels become detectable during sleep. LH and FSH are produced in the anterior pituitary and released due to pulsatile gonadotrophin-releasing hormone (GnRH) secreted by the hypothalamus. There is an increase in the amplitude and frequency of LH secretion as puberty approaches, which causes enlargement of the gonads. In boys, the testicles produce testosterone, and in girls, the ovaries produce oestradiol and ovarian androgens, which, with the adrenal androgens, produce secondary sexual characteristics.Note:The average age at onset of puberty is 11 years in girls. The first sign is breast bud development, followed by the appearance of pubic hair 6–12 months later. Menarche usually occurs 2–2.5 years after breast bud development. Peak height velocity in girls occurs at breast stage 2–3 and virtually always precedes menarche. The onset of puberty in boys is at 11.5 years. The first sign is testicular enlargement (>3 ml) and thinning of the scrotum. This is followed by the pigmentation of the scrotum and growth of the penis, and pubic hair follows. Peak height velocity (growth spurt) is two years later in boys than in girls and occurs at testicular stage 4–5 (i.e. testicular volume 10–12 ml), which is around 13–14 years of age. Breast enlargement occurs in 40–60% of boys (rarely, significant enough to cause social embarrassment in 10%) and is a result of oestradiol produced by the metabolism of testosterone. It usually resolves within three years. During puberty, elongation of the eye often occurs, causing short-sightedness.

Among the given options, pituitary adenoma is an acquired anterior pituitary disorder which represent between 10 and 25% of all intracranial neoplasms.Other options:- Agenesis of the corpus callosum is characterised by the partial or complete absence of the corpus callosum. This condition is associated with pituitary hormone deficiencies.- Congenital disorders such as hydrocephalus or arachnoid cysts may be a cause of precocious puberty.- Pituitary hypoplasia and septo-optic dysplasia are congenital disorders of the pituitary gland.

The patient is most likely to have Bulimia nervosa. A young girl with a low body mass contributes to the low urea. Hypokalaemia and hyponatraemia are due to vomiting. Her urine sodium is also low.- In Addison’s diseases, there are low levels of sodium and high levels of potassium in the blood. In acute adrenal crisis: The most consistent finding is elevated blood urea nitrogen (BUN) and creatinine. Urinary and sweat sodium also may be elevated. – In Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH) there is hyponatremia with corresponding hypo-osmolality, continued renal excretion of sodium, urine less than maximally dilute and absence of clinical evidence of volume depletion.

Somogyi effect presents with night-time hypoglycaemia followed by early-morning hyperglycaemia, hence the glycosuria.

This girl most probably has Turner’s syndrome, which is caused by the absence of one set of genes from the short arm of one X chromosome.Turner syndrome is a lifelong condition and needs lifelong oestrogen replacement therapy. Oestrogen is usually started at age 12-15 years. Treatment can be started with continuous low-dose oestrogens. These can be cycled in a 3-weeks on, 1-week off regimen after 6-18 months| progestin can be added later.In childhood, growth hormone therapy is standard to prevent short stature as an adult.Fetal ovarian development seems to be normal in Turner syndrome, with degeneration occurring in most cases around the time of birth so pulsatile GnRH and luteinising hormone would be of no use.

Androgen insensitivity syndrome (AIS), previously referred to as testicular feminization, is an X-linked disorder in which the patients are genotypically male (possessing and X and Y chromosome) and phenotypically female. This disorder is rare, with reported incidences from 1 in 20,000 to 1 in 60,000 live male births, and is the result of a missing gene on the X chromosome that is responsible for the cytoplasmic or nuclear testosterone receptor. In its absence, the gonad, which is a testis, produces normal amounts of testosterone| however, the end tissues are unable to respond due to the deficient receptors leading to the external genitalia developing in a female fashion. Anti-Mullerian hormone, which is produced by the testis, is normal in these patients, leading to regression of the Mullerian duct. Wolffian duct development, which depends on testosterone, does not occur as the ducts lack the receptors. The cumulative effect is a genotypic male with normal external female genitalia (without pubic or axillary hair), no menses, normal breast development, short or absent vagina, no internal sex organs, and the presence of testis. Frequently, these patients have bilateral inguinal hernias in childhood, and their presence should arouse suspicion of the diagnosis.

Congenital adrenal hyperplasia is a common cause of virilisation in females that can present as ambiguous genitalia at birth. Deficiency of the 21-alphahydroxylase enzyme is implicated in excess mineralocorticoid and androgens produced by the adrenal gland. Virilisation occurs when excess androgens are converted to testosterone in a genetically female foetus, causing the genitalia to resemble male genitalia. A deficiency of 5-alpha hydroxylase would rather decrease the production of testosterone and lead to the presentation of external female genitalia in a genetically male foetus. Autoantibodies against glutamic acid are seen in type 1 diabetes mellitus, while defects in the AIRE gene and the FOXP3 affect components of the immune system.

Precocious puberty refers to the appearance of physical and hormonal signs of pubertal development at an earlier age than is considered normal.Most patients, particularly girls suspected of having central precocious puberty, are otherwise healthy children whose pubertal maturation begins at the early end of the normal distribution curveIn a series of more than 200 patients evaluated at a single medical centre, central precocious puberty occurred 5 times more often in girls than boys.GnRH-dependent precocious puberty is treated with GnRH agonists or Luteinizing Hormone Releasing Hormone (LHRH). Follow up every 4-6 months to ensure that progression of puberty has been arrestedFavourable signs include normalization of accelerated growth, reduction (or at least no increase) in size of breasts, and suppression of gonadotropin levels after a challenge of GnRHThe ideal testing frequency has not been established. Monitor bone age yearly to confirm that the rapid advancement seen in the untreated state has slowed, typically to a half year of bone age per year or less

Puberty is the general term for the transition from sexual immaturity to sexual maturity. There are two main physiological events in puberty:- Gonadarche is the activation of the gonads by the pituitary hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH).- Adrenarche is the increase in production of androgens by the adrenal cortex. It is the term for the maturational increase in adrenal androgen production that normally becomes biochemically apparent at approximately six years of age in both girls and boysA number of other terms describe specific components of puberty:- Thelarche is the appearance of breast tissue, which is primarily due to the action of oestradiol from the ovaries. – Menarche is the time of first menstrual bleed. – Pubarche is the appearance of pubic hair, which is primarily due to the effects of androgens from the adrenal gland. The term is also applied to first appearance of axillary hair, apocrine body odour, and acne.The earliest detectable secondary sexual characteristic on physical examination in most girls is breast/areolar development (thelarche). Ovarian enlargement and growth acceleration typically precede breast development but are not apparent on a single physical examination. Oestrogen stimulation of the vaginal mucosa causes a physiologic leukorrhea, which is a thin, white, non-foul-smelling vaginal discharge that typically begins 6 to 12 months before menarche. Menarche occurs, on average, 2 to 2.5 years after the onset of puberty

Addison disease is adrenocortical insufficiency due to the destruction or dysfunction of the entire adrenal cortex. It affects glucocorticoid and mineralocorticoid function. The onset of disease usually occurs when 90% or more of both adrenal cortices are dysfunctional. The most common symptoms are fatigue, muscle weakness, loss of appetite, weight loss, and abdominal pain. Adrenal insufficiency can be caused by autoimmune disease or suddenly stopping steroid medicines used to treat other conditions, among other causes.

Turner syndrome, a condition that affects only females, results when one of the X chromosomes (sex chromosomes) is missing or partially missing. Turner syndrome can cause a variety of medical and developmental problems, including short height, failure of the ovaries to develop and heart defects.Turner syndrome may be diagnosed before birth (prenatally), during infancy or in early childhood. Occasionally, in females with mild signs and symptoms of Turner syndrome, the diagnosis is delayed until the teen or young adult years.

This child has pseudo hypoparathyroidism. It is a heterogeneous group of rare endocrine disorders characterized by normal renal function and resistance to the action of parathyroid hormone (PTH), manifesting with hypocalcaemia, hyperphosphatemia, and increased serum concentration of PTH.Patients with pseudo hypoparathyroidism type 1a present with a characteristic phenotype collectively called Albright hereditary osteodystrophy (AHO). The constellation of findings includes the following:Short statureStocky habitusObesityDevelopmental delayRound faceDental hypoplasiaBrachymetacarpalsBrachymetatarsalsSoft tissue calcification/ossificationThe goals of therapy are to maintain serum total and ionized calcium levels within the reference range to avoid hypercalcaemia and to suppress PTH levels to normal. This is important because elevated PTH levels in patients with PHP can cause increased bone remodelling and lead to hyper-parathyroid bone disease.The goals of pharmacotherapy are to correct calcium deficiency, to prevent complications, and to reduce morbidity. Intravenous calcium is the initial treatment for all patients with severe symptomatic hypocalcaemia. Administration of oral calcium and 1alpha-hydroxylated vitamin D metabolites, such as calcitriol, remains the mainstay of treatment and should be initiated in every patient with a diagnosis of pseudo hypoparathyroidism.

Congenital hypothyroidism is associated with failure to thrive, macroglossia, prolonged jaundice of a new-born and constipation.

Hypogonadotropic hypogonadismIn Kallmann syndrome: impaired migration of GnRH cells and defective olfactory bulb → ↓ GnRH in hypothalamus → ↓ FSH and ↓ LH → ↓ testosterone and ↓ oestrogenIn hypothalamic and/or pituitary lesions: ↓ pituitary gonadotropins (↓ FSH and ↓ LH) → ↓ testosterone and ↓ oestrogen

Noonan syndrome is a condition that affects many areas of the body. It is characterized by mildly unusual facial features, short stature, heart defects, bleeding problems, skeletal malformations, and many other signs and symptoms.People with Noonan syndrome have distinctive facial features such as a deep groove in the area between the nose and mouth (philtrum), widely spaced eyes that are usually pale blue or blue-green in colour, and low-set ears that are rotated backwards. Affected individuals may have a high-arched palate, poor teeth alignment, and micrognathia. Many children with Noonan syndrome have a short neck, and both children and adults may have excess neck skin (also called webbing) and a low hairline at the back of the neck.Between 50 and 70 % of individuals with Noonan syndrome have short stature. At birth, they are usually a normal length and weight, but growth slows over time. Individuals with Noonan syndrome often have either a pectus excavatum or pectus carinatum. Some affected people may also have scoliosis.Most people with Noonan syndrome have some form of critical congenital heart disease. The most common heart defect in these individuals is pulmonary valve stenosis. Some have hypertrophic cardiomyopathy.A variety of bleeding disorders have been associated with Noonan syndrome. Some affected individuals have excessive bruising, nosebleeds, or prolonged bleeding following injury or surgery. Rarely, women with Noonan syndrome who have a bleeding disorder have excessive bleeding during menstruation (menorrhagia) or childbirth.Adolescent males with Noonan syndrome typically experience delayed puberty. They go through puberty starting at age 13 or 14 and have a reduced pubertal growth spurt that results in shortened stature. Most males with Noonan syndrome have undescended testes (cryptorchidism), which may contribute to infertility (inability to father a child) later in life. Females with Noonan syndrome can experience delayed puberty but most have normal puberty and fertility.Most children diagnosed with Noonan syndrome have normal intelligence, but a few have special educational needs, and some have an intellectual disability. Some affected individuals have vision or hearing problems. It has been estimated that children with Noonan syndrome have an eightfold increased risk of developing leukaemia or other cancers over age-matched peers.

Tanner stage two presents with the following: Downy hair, Breast bud palpable under areola (1st pubertal sign in females).Stage 1 (prepubertal) – elevation of papilla only – no pubic hairStage 2 – breast bud forms – sparse, slightly pigmented hair on labia majoraStage 3 – Breast begins to become elevated, extends beyond areola borders – hair becomes more coarse and curlyStage 4 – increased size and elevation. Areola and papilla form secondary mound – adult like, but sparing medial thighsStage 5 – final size, areola returns but papilla remains projected – hair extends to medial thighs

Diabetes insipidus (DI) is defined as the passage of large volumes (>3 L/24 hr) of dilute urine (< 300 mOsm/kg). It has the following 2 major forms:Central (neurogenic, pituitary, or neurohypophyseal) DI, characterized by decreased secretion of antidiuretic hormone (ADH| also referred to as arginine vasopressin [AVP])Nephrogenic DI, characterized by decreased ability to concentrate urine because of resistance to ADH action in the kidney.The boy most probably has nephrogenic diabetes insidious (DI) not central DI so he is not responding to the ADH treatment.

Intensive physical training and participation in competitive sports during childhood and early adolescence may affect athletes’ pubertal development.Female athletes who do not begin secondary sexual development by the age of 14 or menstruation by the age of 16 warrant a comprehensive evaluation and treatment.Since she is still 14, adequate diet and observation are enough.

The adult height potential may be calculated for a male child by (father’s height in cm + mother’s height in cm) / 2 then add 7 cm.In the scenario provided: (170 + 150)/2 + 7 = 167 cm = 1.67 m.For a female child by (father’s height in cm + mother’s height in cm) / 2 then minus 7 cm.This can then be plotted on a height centile chart to find the mid-parental centile.Causes of short stature include:- Normal variant (often familial)- Constitutional delay of growth and puberty- Chronic illness, e.g. cystic fibrosis, inflammatory bowel disease- Endocrine: growth hormone deficiency, hypothyroidism, steroid excess syndromes: Turner’s, Down’s, Prader-Willi- Skeletal dysplasias, e.g. achondroplasia

WHO states that diabetes can be diagnosed from a single fasting glucose of > 7.0 mmol/l with characteristic symptoms or a glucose level of > 11.1 mmol/l 2 hours after a glucose load. Two fasting glucose levels of > 7.0 mmol/l on separate occasions can also fit the diagnosis in the absence of characteristic symptoms.

The most probable diagnosis for this boy is primary hypothyroidism.Rationale:The development of secondary sexual characteristics in a boy aged less than 9 years of age is highly suggestive of precocious puberty.Around 80% of boys with precocious puberty have pathological causes and require detailed investigation. In this case, the child has long-standing short stature but coupled with the early puberty and delay in bone age, the diagnosis is primary hypothyroidism, which is the only cause of this clinical picture.

Among the given options, Di-George syndrome is not associated with adrenal gland disorders.Di-George syndrome is characterised by distinct facial features (micrognathia, cleft palate, short philtrum, and low-set ears), hypocalcaemia, mental retardation, cardiac defects (especially tetralogy of Fallot), and immune deficiencies.A useful memory aid is CATCH-22:- Cardiac defects- Abnormal facial features- Thymic aplasia/hypoplasia- Cleft palate- Hypocalcaemia/Hypoparathyroidism- 22 – Due to 22q11 deletionOther options:- Addison’s disease is a result of adrenal hypofunction and may present with collapse secondary to a salt-losing crisis.- Congenital adrenal hyperplasia: CAH is caused by the deficiency of an enzyme (classically 21-hydroxylase deficiency) in the biosynthetic pathway in the adrenal cortex, leading to insufficient production of cortisol and aldosterone, and a build-up of 17-hydroxyprogesterone.- Cushing’s syndrome is a syndrome of cortisol excess. An adrenal tumour is a primary cause.- Pheochromocytoma is a catecholamine releasing tumour of the adrenal gland/s.

Puberty is when a child’s body begins to develop and change as they become an adult.The average age for girls to begin puberty is 11, while for boys the average age is 12.It’s completely normal for puberty to begin at any point from the ages of 8 to 14. The process can take up to 4 years.

The first sign of pubarche in females is breast-bud development (thelarche).This begins between the ages of 9 and 12 years and continues to 12–18 years. Pubic hair growth occurs next (said to occur in stage 3), at ages 9–14 years, and is complete at 12–16 years. Menarche occurs relatively late in stage 4 (age 11–15 years) and is associated with a deceleration in growth. The peak height velocity is reached earlier (10–13 years) and growth is completed much earlier than in boys.

While the clinical scenario and the anosmic presentation of the child are highly suggestive of Kallmann’s syndrome, reduced testosterone, FSH and LH levels can confirm the diagnosis.Kallman’s syndrome is a recognised cause of delayed puberty secondary to hypogonadotropic hypogonadism. It is usually inherited as an X-linked recessive trait. Kallman’s syndrome is thought to be caused by a failure of GnRH-secreting neurons to migrate to the hypothalamus.Clinical features of Kallmann’s syndrome include:- Delayed puberty- Hypogonadism, cryptorchidism- Anosmia- Low sex hormone levels – Inappropriately low/normal LH and FSH levels- Some patients can present with associated cleft lip/palate and visual/hearing defects.

Findings described are suggestive of Waterhouse-Friderichsen syndrome which develops secondary to meningococcaemia. The reported incidence of Addison’s disease is 4 in 100,000. It affects both sexes equally and is seen in all age groups. It tends to show clinical symptoms at the time of metabolic stress or trauma. The symptoms are precipitated by acute infections, trauma, surgery or sodium loss due to excessive perspiration.

Graves disease is an autoimmune disorder in which patients present with thyrotoxicosis and related ophthalmopathy, and dermopathy. Many affected patients experience hyperthyroidism. Peak incidence of graves disease is after the 3rd decade of life and is more common in women than in men. Graves susceptibility is association with HLA-DR3. Clinical features of Graves disease include an increased metabolic rate, heat intolerance, irritability, weight loss despite increasing appetite, diarrhoea palpitations, chemosis, acropachy and onycholysis.