The azygos lobe is usually well seen on the chest radiograph, where it is limited by the azygos fissure, a fine, convex (relative to the mediastinum) line that crosses the apex of the right lung.

From the given clinical scenario, the peroxisomal disorder in question is Refsum’s disease.It is characterised by anosmia, early-onset retinitis pigmentosa (night blindness), chronic ataxia, variable neuropathy, deafness and ichthyosis. It is an inherited disorder of fatty acid oxidation with phytanic acid accumulation in the blood and tissues. This leads to the motor and sensory neuropathy. Other options:- Loss of sensation in extremities, dysarthria and diabetes is suggestive of Friedrich’s Ataxia. It is the most common autosomal recessive cause of ataxia. Associated features include dysarthria, scoliosis, diabetes and hypertrophic cardiomyopathy. – Numbness of the limbs, seizures and developmental delay suggests mitochondrial cytopathy such as NARP (Neuropathy, Ataxia and Retinitis Pigmentosa). Learning difficulties, developmental delays and convulsions are not uncommon, as with many mitochondrial disorders. – Rapid, chaotic eye movements, behaviour change and irritability, suggest opsoclonus-myoclonus syndrome. It is thought to be a Para infectious or paraneoplastic condition (secondary to neuroblastoma) linked to an abnormal immune response. Children present unwell with altered behaviour, irritability, ataxia, random chaotic eye movements and later myoclonus. – Sweet-smelling urine, lethargy and seizures suggest Maple Syrup Urine Disease (MSUD). It is an autosomal recessive organic acidaemia. There is a distinct sweet odour to the urine of affected individuals, particularly at times of acute illness. Without treatment, MSUD can lead to seizures, brain damage, coma and death. The most common and classic form affects babies shortly after birth, but variant forms may not be evident until later childhood.

The right testicular vein is a tributary of the inferior vena cava, while the left testicular vein drains into the left renal vein.Note:The testicular venous drainage begins in the septa and these veins together with those of the tunica vasculosa converge on the posterior border of the testis as the pampiniform plexus. The pampiniform plexus, in turn, drains to the testicular vein.

Live attenuated vaccines such as the MMR, should be avoided in HIV+ patients.

The clinical presentation of the boy suggests the involvement of the right frontal lobe.Psychiatric or behavioural disturbances secondary to frontal lobe lesions exhibit lateralisation. The lesions of the left hemisphere are associated with depression, especially if the lesion involves the dorsolateral portion of the prefrontal cortex. Whereas, lesions of the right hemisphere are associated with impulsivity, disinhibition, and aggression, as it is the case with the child in question.Presenting symptoms of lobar dysfunctions:- Frontal lobe: Contralateral hemiplegia, impaired problem solving, disinhibition, and lack of initiative. Broca’s aphasia and agraphia suggest the involvement of the dominant hemisphere.- Temporal lobe: Wernicke’s aphasia (dominant hemisphere involvement), homonymous upper quadrantanopia and auditory agnosia (non-dominant hemisphere involvement).- Parietal lobe: Anosognosia, dressing apraxia, spatial neglect and constructional apraxia are observed when the non-dominant hemisphere is involved. Gerstmann’s syndrome is observed when the dominant hemisphere is involved.- Occipital lobe: Visual agnosia, visual illusions and contralateral homonymous hemianopia.

Projectile vomiting is the hallmark symptom of hypertrophic pyloric stenosis. It is the most common cause of intestinal obstruction in infancy, which has a male-to-female predominance of 4-5:1. Current management recommendations include ultrasonography for diagnosis, correction of electrolytes, and surgical intervention.

The spinal cord ends at L3 in the new-bornmigrates cephalad during childhood to end at L1 – L2 and reaches adult size by the age of 10.

The cells in the testes that secrete testosterone are the Leydig cells.Other cells in testes include:- Spermatogonia: These are undifferentiated male germ cells which undergo spermatogenesis in the seminiferous tubules of the testes.- Sertoli cells: They are a part of the seminiferous tubule of the testes, cells are activated by FSH and nourish developing sperm cells.- Myoid: They are squamous contractile cells which generate peristaltic waves, they surround the basement membrane of testes.- Fibroblasts: Cells which synthesise collagen and the extracellular matrix.

As her paracetamol level is under the required treatment threshold, she requires no medical treatment. However, she has taken a simultaneous drug overdose and excessive alcohol consumption. These two factors together require psychiatric evaluation and so she should be referred to the psychiatry ward.

Benign neonatal sleep myoclonus (BNSM) is a disorder commonly mistaken for seizures during the new-born period. It is characterized by myoclonic lightninglike jerks of the extremities that exclusively occur during sleep| it is not correlated with epilepsy.Causes of neonatal seizures:Hypoxic-ischemic encephalopathy: Hypoxic-ischemic encephalopathy disrupts the ATP-dependent sodium-potassium pump and appears to cause excessive depolarization.Intracranial haemorrhage: occurs more frequently in premature than in term infants. Subarachnoid haemorrhage is more common in term infants. This type of haemorrhage occurs frequently and is not clinically significant. Typically, infants with subarachnoid haemorrhage appear remarkably well. Metabolic disturbances include hypoglycaemia, hypocalcaemia, and hypomagnesemia. Less frequent metabolic disorders, such as inborn errors of metabolism, are seen more commonly in infants who are older than 72 hours. Typically, they may be seen after the infant starts feeding.Intracranial infections (which should be ruled out vigorously) that are important causes of neonatal seizures include meningitis, encephalitis (including herpes encephalitis), toxoplasmosis, and cytomegalovirus (CMV) infections. The common bacterial pathogens include Escherichia coli and Streptococcus pneumoniae.Cerebral malformationsBenign neonatal seizures

A peripheral blood film in iron deficiency anaemia can reveal the following morphologically variant RBCs:- Microcytic cells- Hypochromic cells- Pencil cells- Target cellsOther options:- Schistocytes can be caused by mechanical heart valves. – Rouleaux can be seen in chronic liver disease and malignant lymphoma. – Tear-drop poikilocytes can be seen in myelofibrosis. – Acanthocytes can be seen in liver disease and McLeod blood group phenotype.Pathological red cell forms include:- Target cells: Sickle-cell/thalassaemia, iron-deficiency anaemia, hyposplenism, and liver disease.- Tear-drop poikilocytes: Myelofibrosis- Spherocytes: Hereditary spherocytosis and autoimmune haemolytic anaemia- Basophilic stippling: Lead poisoning, thalassaemia, sideroblastic anaemia, and myelodysplasia- Howell-Jolly bodies: Hyposplenism- Heinz bodies: G6PD deficiency and alpha-thalassaemiaSchistocytes (‘helmet cells’): Intravascular haemolysis, mechanical heart valve, and disseminated intravascular coagulation- Pencil poikilocytes: Iron deficiency anaemia- Burr cells (echinocytes): Uraemia and pyruvate kinase deficiency – Acanthocytes: Abetalipoproteinemia

Group B beta-haemolytic Streptococcus (GBS) and Escherichia coli are the most common cause of early sepsis. Group B Streptococcus (GBS), also known as Streptococcus agalactiae, is best known as a cause of postpartum infection and as the most common cause of neonatal sepsis. The GBS organism colonizes the vagina, GI tract, and the upper respiratory tract of healthy humans. GBS infection is almost always associated with underlying abnormalities. In elderly persons aged 70 years or older, GBS infection is strongly linked with congestive heart failure and being bedridden.Penicillin remains the drug of choice for group B streptococcal infection but resistance may occur.

Recurrent bacterial infections may be due to lack of B-cell function, consequently resulting in a lack of gamma globulins production. Once the maternal antibodies have depleted, the disease manifests with greater severity and is called x-linked agammaglobulinemia also known as ‘X-linked hypogammaglobulinemia’, ‘XLA’ or ‘Bruton-type agammaglobulinemia. it is a rare x linked genetic disorder that compromises the bodies ability to fight infections.
Acute leukaemia causes immunodeficiency but not so specific.
DiGeorge syndrome is due to lack of T cell function.
Aplastic anaemia and EBV infection does not cause immunodeficiency.

The parotid duct (Stensen’s duct), which provides an exit for the gland’s secretions, passes through the anterior edge of the gland in the superficial lobe, turns medially at the anterior border of the masseter, penetrates the buccinator, then enters the oral cavity lateral to the second maxillary molar.

Cataracts in infants are most commonly identified by an abnormal red reflex. Due to the high risk of amblyopia in unilateral cataracts, prompt referral to a paediatric ophthalmologist is indicated. Bilateral cataracts may occur in association with several syndromes or diseases, and these children require evaluation for these systemic disorders.Retinoblastoma is rare, but it is the most common primary intraocular tumour in children. About 80% of cases are diagnosed before age 4, with a median age at diagnosis of 2 years. It most frequently presents due to an abnormal red reflex. It is one of the few life-threatening disorders encountered in paediatric ophthalmology. Intraocular retinoblastoma is very treatable, but the mortality for metastatic disease is high. Identification of tumours before systemic spread is critical. Most children with large unilateral tumours will require enucleation (surgical removal of the eye), but the eye and vision may sometimes be preserved if the tumours are identified when they are small.

Many of the symptoms favour blast cells: the patient’s young age| a reoccurring sore throat caused by neutropenia and abnormal lymphoblasts| pale conjunctiva due to reduced production of red blood cells (this is because the marrow has been occupied by blast cells). There are no risk factors present for aplastic anaemia, and congenital aplastic anaemia would present itself earlier in life. A bone marrow aspiration would be needed to confirm the diagnosis.

Among the options provided, bradycardia is a feature of raised intracranial pressure.The features of raised intracranial pressure include relative bradycardia and hypertension, altered consciousness, focal neurology and seizures.All other options are signs of shock but not raised intracranial pressure.

Juvenile angiofibroma (JA) is a rare benign vascular lesion of the skull base that affects young adolescent males. The management of JA is challenged by the abundant vascular blood supply of the lesion, along with the complex anatomy of the skull base and the young age of the affected population. JA typically affects the male population, most commonly between 9 and 19 years of age. The most frequent symptoms are nasal obstruction and epistaxis. Nasal obstruction may be bilateral despite the unilaterality of the lesion, due to nasopharyngeal extension as well as deviation of the nasal septum by the expansile lesion. Epistaxis is usually brisk and intermittent. Purulent nasal discharge and facial pain can be due to sinus drainage pathway obstruction, and conductive hearing loss indicates obstruction of the eustachian tube.

According to NICE guidelines:Do not offer lithium to women who are planning a pregnancy or pregnant, unless antipsychotic medication has not been effective.If antipsychotic medication has not been effective and lithium is offered to a woman who is planning a pregnancy or pregnant, ensure:the woman knows that there is a risk of fetal heart malformations when lithium is taken in the first trimester, but the size of the risk is uncertain. Lithium levels may be high in breast milk with a risk of toxicity for the baby.If a woman taking lithium becomes pregnant, consider stopping the drug gradually over 4 weeks if she is well. Explain to her that:stopping the medication may not remove the risk of fetal heart malformations and there is a risk of relapse, particularly in the postnatal period, if she has bipolar disorder.If a woman taking lithium becomes pregnant and is not well or is at high risk of relapse, consider:switching gradually to an antipsychotic or stopping lithium and restarting it in the second trimester (if the woman is not planning to breastfeed and her symptoms have responded better to lithium than to other drugs in the past) or continuing with lithium if she is at high risk of relapse and an antipsychotic is unlikely to be effective. If a woman continues taking lithium during pregnancy:- check plasma lithium levels every 4 weeks, then weekly from the 36th week. Adjust the dose to keep plasma lithium levels in the woman’s therapeutic range- ensure the woman maintains an adequate fluid balance- ensure the woman gives birth in the hospital- ensure monitoring by the obstetric team when labour starts, including checking plasma lithium levels and fluid balance because of the risk of dehydration and lithium toxicity- stop lithium during labour and check plasma lithium levels 12 hours after her last dose.

Time and EventWeek 1: ImplantationWeek 2: Formation of bilaminar diskWeek 3: Formation of primitive streakFormation of notochordGastrulationWeek 4: Limb buds begin to formNeural tube closesHeart begins to beatWeek 10: Genitals are differentiated

The most probable diagnosis for this patient would be torsion of a hydatid cyst of the testis.Note:The differential diagnoses in acute testicular pain/swelling are listed in the possible answers. Testicular torsion typically affects adolescent males and presents with acute painful swelling and a horizontally lying testicle. Other options:- Epididymo-orchitis is diagnosed during surgery when a thickened erythematous epididymis is noted. Ectopic ureteric insertion into the vas must be excluded by ultrasound scan on an out-patient basis. The hydatid cyst or cyst of Morgagni represents the remnants of the Mullerian structure. In the pre-pubertal child, a surge in hormones can stimulate growth and chance of torsion. It is diagnosed by surgical exploration or by a blue dot sign. Idiopathic scrotal oedema tends to be within the scrotum itself, and the testis can be examined in the groin to exclude pain in the testis. All acute scrotal pain must be explored to exclude testicular torsion unless a surgical registrar is convinced of a torted hydatid cyst.- An 8-year-old is more likely to present with a torted hydatid cyst. The blue dot sign is diagnostic and can negate the need for surgical exploration. The age of the child also makes epididymo-orchitis less likely.- Idiopathic scrotal oedema presents with an erythematous and thickened scrotum. This can cross the midline and involve the whole scrotum.- Finally, an inguinal hernia would present with a mass in the groin extending to the scrotum that you cannot get above.

PARACHUTE REFLEX: This reflex occurs in slightly older infants when the child is held upright and the baby’s body is rotated quickly to face forward (as in falling). The baby will extend his arms forward as if to break a fall, even though this reflex appears long before the baby walks.Newborn reflexes are:Rooting reflex:This reflex starts when the corner of the baby’s mouth is stroked or touched. The baby will turn his or her head and open his or her mouth to follow and root in the direction of the stroking. This helps the baby find the breast or bottle to start feeding. This reflex lasts about 4 months.Suck reflex:Moro reflex:The Moro reflex is often called a startle reflex. That’s because it usually occurs when a baby is startled by a loud sound or movement. In response to the sound, the baby throws back his or her head, extends out his or her arms and legs, cries, then pulls the arms and legs back in. This reflex lasts until the baby is about 2 months old.Tonic neck reflex:When a baby’s head is turned to one side, the arm on that side stretches out and the opposite arm bends up at the elbow. This is often called the fencing position. This reflex lasts until the baby is about 5 to 7 months old.Grasp reflex:Stroking the palm of a baby’s hand causes the baby to close his or her fingers in a grasp. The grasp reflex lasts until the baby is about 5 to 6 months old. A similar reflex in the toes lasts until 9 to 12 months.Stepping reflex:This reflex is also called the walking or dance reflex because a baby appears to take steps or dance when held upright with his or her feet touching a solid surface. This reflex lasts about 2 months.

18-month-old milestonesSocial and EmotionalLikes to hand things to others as play May have temper tantrums May be afraid of strangers Shows affection to familiar people Plays simple pretend, such as feeding a doll May cling to caregivers in new situations Points to show others something interesting Explores alone but with parent close by Language/CommunicationSays several single words Says and shakes head “no” Points to show someone what he wants Cognitive (learning, thinking, problem-solving)Knows what ordinary things are for| for example, telephone, brush, spoon Points to get the attention of others Shows interest in a doll or stuffed animal by pretending to feed Points to one body part Scribbles on his own Can follow 1-step verbal commands without any gestures| for example, sits when you say “sit down” Movement/Physical DevelopmentWalks alone May walk up steps and run Pulls toys while walking Can help undress herself Drinks from a cup Eats with a spoon

Infective endocarditis (IE) is caused by a bacterial, or fungal infection which damages the heart’s endothelium and can thus lead to changes in heart function, valve incompetencies, possible cardiac failure, as well other associated skin and organ changes. Organisms common in IE include Staphylococcus aureus and Streptococcus viridians. The HACEK organisms (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella species) are common in neonates. The Duke criteria uses 2 major, or 1 major and 3 minor criteria, or 5 minor criteria to diagnose infective endocarditis. Major criteria include:- a positive blood culture and evidence of endocardial involvement. Minor criteria include: – evidence of predisposition (a heart condition of injection drug use)- a fever- vascular phenomena such as Janeway lesions- immunologic phenomena such as Osler’s nodes and Roth’s spots| and- microbiological or serological evidence of active infection.

Also known as the hyoid arch, it forms the side and front of the neck. From its cartilage develops the styloid process, stylohyoid ligament and lesser cornu of the hyoid bone. The muscular derivatives include the muscles of facial expression, stapedius, stylohyoid and the posterior belly of the digastric. All these are innervated by cranial nerve VII but migrate into the area of the mandibular arch.

Transposition of the great arteries (TGA) is a common congenital heart lesion that presents with severe cyanosis that is likely to appear in the first day of life.

Three physical changes – breast budding, pubic hair growth, and axillary hair growth in the order mentioned precede menarche. These changes are due to oestrogen, a hormone essential for pubertal development.The various pubertal changes in males include:-Testicular growth: It is the first sign of puberty occurring at around 12 years of age (Range = 10 – 15 years).- Testicular volume: An increase in the volume of testicles to 4 ml indicates the onset of pubertyThe various pubertal changes in females include:- The first sign is breast development at around 11.5 years of age (range = 9-13 years)- Followed by the onset of height spurt reaching the maximum in puberty (at 12 years of age)- The final change that occurs is termed menarche at 13 (11-15) years of age.Some of the other pubertal changes include:- Gynecomastia may develop in boys- Asymmetrical breast growth may occur in girls- Diffuse enlargement of the thyroid gland

After a period of 14 days, if jaundice persists in a term new-born, having ruled out the other possibilities, biliary atresia should be considered as a possible diagnosis.Biliary atresia is a rare but serious condition. Symptoms include obstructive jaundice (dark urine and pale stool). Management:Surgery within 8 weeks is recommended. Survival is around 90% using current treatment regimes. Without treatment, children will survive to around 18 months.

Acute lymphoblastic leukaemia (ALL) is an aggressive type of blood and bone marrow cancer which can appear in childhood. Signs of childhood ALL include: Fever, Easy bruising, Petechiae, Bone or joint pain, Painless lumps in multiple areas of the body, Weakness, fatigue or paleness, and Loss of appetite. Blood tests may show elevated white blood cells, decreased values of red blood cells and low platelet count.

A preterm with respiratory distress syndrome presents with the condition as a result of immature lungs and inadequate surfactant production. Management of RDS therefore includes surfactant therapy, oxygen administration and mechanical ventilation, as well as measures such maintaining acid base levels and blood haemoglobin in an intensive care unit. Dexamethasone is not shown to be particularly effective when given to a preterm, but can however be used to prevent or decrease RDS severity when given to the mother before delivery.