HbA1c stands for glycated haemoglobin. In patients with haemolytic diseases associated with a shortened RBC survival, HbA1c levels can be unusually low despite controlled diabetes mellitus.These haemolytic diseases can include glucose-6-phosphate dehydrogenase deficiency and sickle cell anaemia.HbA1c:It is a measure of non-enzymatic glycation which occurs due to haemoglobin’s exposure to plasma glucose. As plasma glucose increases so does HbA1c.The level of HbA1c quantitively assesses the control of diabetes mellitus over the last 120 days (as this is the life span of a red blood cell).Haemoglobin type A is separated on cation exchange chromatographyOther subsections include HbA1O, HbA1a, HbA1b.According to the updated NICE recommendations (2015):The target level of HbA1c in children with T1DM is 48 mmol/mol (6.5%) or lower. It is monitored every three months. Better control is associated with fewer long term complications

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.

Bone age is used to determine the maturation of a child’s bones’ and is used to detect pathological growth. This is done using the X-ray of the wrist. Several conditions can either advance or delay the bone age such that they may not match the child’s chronological age. Bone age is advanced in conditions where there are prolonged or elevated sex hormone levels such as precocious puberty, or in genetic overgrowth conditions such as Beckwith-Wiedemann syndrome. Bone age is delayed in constitutional growth delay, chronic ill health, endocrine disorders such as growth hormone deficiencies or hypothyroidism, genetic disorders such as Trisomy 21, Trisomy 18, and Turner’s syndrome. Obesity is unlikely to cause growth delay.

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 a period of transitioning into adulthood by developing full reproductive potential by undergoing drastic physiological and psychological changes. For boys, it occurs around 9-16 years of age typically. The process of pubertal changes is usually divided into stages called tanner’s stages. The physiologic changes of puberty are initiated by the release of gonadotropin-releasing hormones from the hypothalamus, which then interact with numerous endogenous and environmental stimuli to bring about the physical pubertal features. Tanner stage 2 in boys is characterized by the thinning and reddening of the scrotal skin.The growth spurt of around 9cm per year is expected in boys, at the peak velocity.Testicular enlargement of >3cm commences puberty.Pubarche, in the absence of other secondary sexual characteristics, is pathological.Adrenarche is the increase in the secretion of adrenal androgens, occurring prior to increased gonadotropin release.

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.

The child has experienced the Somogyi phenomenon. It is a phenomenon where there’s a morning rise in blood sugar. Often it occurs as posthypoglycemic hyperglycaemia and follows nocturnal hypoglycaemia. The mechanism is the production of counter-regulatory hormones like glucagon, cortisol and adrenaline, which increase glucose. She can be managed by reducing her evening insulin dosage and increasing complex carbohydrates for supper (evening meal).Type I diabetes mellitus:It is a chronic illness that is characterised by the inability to produce insulin. It is caused by autoimmune destruction of the beta cells in the pancreas and often presents with ketoacidosis.The patient can present with symptoms suggestive of polyuria, polydipsia, and weight loss. There can be periods of islet cell regeneration in these patients, which leads to a ‘honeymoon period’ of remission.Symptoms occur when there is < 20% of islet cell activity left.Insulin therapy is required in almost all children with type 1 diabetes.Most children require multiple insulin injections throughout the day via subcutaneous insulin pumps.Target HbA1c in these patients is 48 mmol/mol according to the updated NICE guidelines.

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.

Individuals with Marfan syndrome are usually tall and slender, have elongated fingers and toes (arachnodactyly), loose joints, and have an arm span that exceeds their body height. Other common features include a long and narrow face, crowded teeth, an abnormal curvature of the spine (scoliosis or kyphosis), stretch marks (striae) not related to weight gain or loss, and either a sunken chest (pectus excavatum) or a protruding chest (pectus carinatum). Some individuals develop an abnormal accumulation of air in the chest cavity that can result in the collapse of a lung (spontaneous pneumothorax). A membrane called the dura, which surrounds the brain and spinal cord, can be abnormally enlarged (dural ectasia) in people with Marfan syndrome. Dural ectasia can cause pain in the back, abdomen, legs, or head. Most individuals with Marfan syndrome have some degree of near-sightedness (myopia). Clouding of the lens (cataract) may occur in mid-adulthood, and increased pressure within the eye (glaucoma) occurs more frequently in people with Marfan syndrome than in those without the condition.

In boys, the first manifestation of puberty is testicular enlargement| the normal age for initial signs of puberty is 9 to 14 years in males. Pubic hair in boys generally appears 18 to 24 months after the onset of testicular growth and is often conceived as the initial marker of sexual maturation by male adolescents.

Precocious Puberty is the development of secondary sexual characteristics before the age of 8 in females, and 9 in males. The first sign of early puberty in males is testicular enlargement, followed by growth of the penis and the scrotum at least a year after. Precocious puberty in boys in uncommon and usually has an organic cause leading to excess secretion of testosterone. These can be gonadotrophin dependent in the case of an inter cranial lesion, where the testes would be bilaterally enlarged, or from excess production from the adrenal gland in the case of adrenal hyperplasia or a tumour.

Klinefelter’s syndrome: The low follicle-stimulating hormone (FSH) and luteinising hormone (LH), together with the low testosterone, suggests a hypogonadotropic hypogonadism. We know that there is no mental retardation, and we are told that physical examination is normal and sense of smell would usually not be tested. Consequently a diagnosis of Kallman’s is suggested. We are not told of a family history of growth delay, thus this is unlikely to be constitutional delay. The thyroid-stimulating hormone (TSH) is normal, making hypothyroidism unlikely and this together with the normal prolactin make hypopituitarism most unlikely.

Precocious puberty is the development of secondary sexual characteristics before the age of 8 in females, and 9 in males. The first sign of early puberty in females is breast enlargement, followed by the appearance of pubic and axillary hair, and finally menarche, 2-3 years after the onset of thelarche. Precocious puberty is caused by the premature activation of the hypothalamic-pituitary-gonadal axis where FSH and LH levels are raised. Less common is the gonadotrophin independent form, which is due to excess sex hormones, but low FSH and LH levels.

Based on the clinical scenario, the most probable diagnosis in this patient is Kallmann’s syndrome.Kallmann’s syndrome is due to isolated gonadotrophin-releasing hormone (GnRH) deficiency. It is often inherited in an X-linked recessive manner. Other options:- While Klinefelter’s syndrome is also associated with hypogonadism, the other clinical features of Klinefelter’s are not seen. – Cryptorchidism is ruled out by the presence of testes in the scrotum. – The presentation of the child is not suggestive of mumps orchitis or hyperprolactinaemia.

Retinopathy screening need not be done on an annual basis for a 9-year-old child. Screening for diabetic retinopathy should begin at the age of 12.Diabetes mellitus is an increasing problem in both developing and developed countries alike. Some of the risk factors include:ObesityFamily historyFemale sex Asian and African racesPresence of acanthosis nigricans is seen with type 2 but not type 1 diabetesThe diagnosis is mostly incidental or subacute.The treatment aims are good blood sugar control, maintenance of normal BMI, and reduction of complications. The treatment modality also includes lifestyle modifications and cessation of smoking. Even after all this, diabetic ketoacidosis can still occur.Management of diabetes mellitus – NICE guidelines (Updated, 2015): – Standard release metformin should be offered from the moment of diagnosis.- HBA1c should be measured every three months. The target HBA1c level of 48 mmol/mol (6.5%) or lower is ideal for minimising the risk of long term complications.- Children should undergo an eye examination by an optician every two years.- Annual immunisation against influenza and pneumococcal infections are essential.- There is an increased risk of psychological and psychosocial difficulties if the child with type 1 diabetes is on insulin or oral hypoglycaemic medications. These include anxiety disorder, depression, behavioural and conduct disorders and family conflict.- Annual monitoring to be done for:Hypertension starting at diagnosis.Dyslipidaemia starting at diagnosis.Screening for microalbuminuria starting at diagnosis.Diabetic retinopathy from 12 years of age.

The patient has features of type 1 diabetes mellitus, a disease of autoimmune aetiology. This also puts the patient at risk of developing other autoimmune disorders like Addison’s disease, Grave’s disease, and coeliac disease.All of the other options are non-autoimmune disorders.Diabetes mellitus is an increasing problem in both developing and developed countries alike.Some of the risk factors include:ObesityFamily historyFemale sex Asian and African racesPresence of acanthosis nigricans is seen with type 2 but not type 1 diabetesThe diagnosis is mostly incidental or subacute.The treatment aims are good blood sugar control, maintenance of normal BMI, and reduction of complications. The treatment modality also includes lifestyle modifications and cessation of smoking.Even after all this, diabetic ketoacidosis can still occur.Management of diabetes mellitus – NICE guidelines (Updated, 2015): – Standard release metformin should be offered from the moment of diagnosis.- HBA1c should be measured every three months. The target HBA1c level of 48 mmol/mol (6.5%) or lower is ideal for minimising the risk of long term complications.- Children should undergo an eye examination by an optician every two years.- Annual immunisation against influenza and pneumococcal infections are essential.- There is an increased risk of psychological and psychosocial difficulties if the child with type 1 diabetes is on insulin or oral hypoglycaemic medications. These include anxiety disorder, depression, behavioural and conduct disorders and family conflict.- Annual monitoring to be done for:Hypertension starting at diagnosis.Dyslipidaemia starting at diagnosis.Screening for microalbuminuria starting at diagnosis.Diabetic retinopathy from 12 years of age.

Bone age is a valuable tool for determining the skeletal maturation in children. An X-ray of the left hand and wrist or knee is used to calculate bone age, which is then compared with the chronological age of the subject to know if the bone age is advanced or delayed. Certain standardized methods are used to score skeletal maturity, the most common methods are the Tanner-Whitehouse (TW) and Greulich-Pyle (GP) methods. The growth plate comprises a resting zone, a proliferative zone, hypertrophic cartilage zone, calcified cartilage zone, and then the ossification zone. This is the zonal distribution from the epiphysis to the diaphysis. After the closure of growth plates, spinal growth still occurs to some extent, adding up to the final height. The growth plates in boys close at around 17 to 19 years of age, while in girls, they close at around 13 to 15 years.

Lypohypertrophy is the most common skin-related complication of insulin injection.

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

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.

A bone age study helps doctors estimate the maturity of a child’s skeletal system. It’s usually done by taking a single X-ray of the left wrist, hand, and fingers. It is a safe and painless procedure that uses a small amount of radiation. The bones on the X-ray image are compared with X-rays images in a standard atlas of bone development, which is based on data from large numbers of other kids of the same gender and age. The bone age is measured in years.

Zona fasciculata of the adrenal produces the maximum levels of cortisol in the body.Functions of cortisol:- Increases blood pressure: permits normal response to angiotensin II and catecholamines by up-regulating alpha-1 receptors on arterioles.- Inhibits bone formation: decreases osteoblasts, type 1 collagen and absorption of calcium from the gut, and increases osteoclastic activity.- Increases insulin resistance.- Increases gluconeogenesis, lipolysis and proteolysis.- Inhibits inflammatory and immune responses.- Maintains function of skeletal and cardiac muscle.An excess of corticosteroids in the body causes various symptoms that are a part of Cushing’s syndrome.

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.

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 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.

Deficiency of 21-hydroxylase, resulting from mutations or deletions of CYP21A, is the most common form of Congenital Adrenal Hyperplasia, accounting for more than 90% of cases.Females with mild 21-hydroxylase deficiency are identified later in childhood because of precocious pubic hair, clitoromegaly, or both, often accompanied by accelerated growth and skeletal maturation (simple virilizing adrenal hyperplasia)Diagnosis of 21-hydroxylase deficiency: High serum concentration of 17-hydroxyprogesterone (usually >1000 ng/dL) and urinary pregnanetriol (metabolite of 17-hydroxyprogesterone) in the presence of clinical features suggestive of the disease| 24-hour urinary 17-ketosteroid levels are elevated

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.

The average age for girls to begin puberty is 11.The first sign of puberty in girls is usually that their breasts begin to develop.It’s normal for breast buds to sometimes be very tender or for one breast to start to develop several months before the other one.Pubic hair also starts to grow, and some girls may notice more hair on their legs and arms.After a year or so of puberty beginning, and for the next couple of years:girls’ breasts continue to grow and become fuller.Around 2 years after beginning puberty, girls usually have their first period,pubic hair becomes coarser and curlierunderarm hair begins to grow. From the time their periods start, girls grow 5 to 7.5cm (2 to 3 inches) annually over the next year or two, then reach their adult height.After about 4 years of puberty in girls:breasts become adult-likepubic hair has spread to the inner thighgenitals should now be fully developedgirls stop growing taller.

Hypogonadism is found to be a feature in gigantism also known as acromegaly, a condition caused by growth hormone abnormalities. The most common cause of gigantism is a pituitary adenoma. Hypogonadism exists among other endocrinopathies found in gigantism. Other causes of hypogonadism include Kleinfelter’s syndrome, which is characterized by premature testicular failure. The other options listed, primary hypothyroidism, teratoma, tuberous sclerosis and hepatoblastoma are all associated with precocious puberty.

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