Mumps presents with a prodromal phase of general malaise and fever. On examination there is usually painful parotid swelling which has high chances of becoming bilateral. In OM with effusion there are no signs of infection and the only symptom is usually hearing loss. Acute otitis externa produces otalgia as well as ear discharge and itching. Acute OM produces otalgia and specific findings upon otoscopy. In acute mastoiditis the patient experiences ear discharge, otalgia, headache, hearing loss and other general signs of inflammation.

Marfan syndrome is a disorder that affects the connective tissue found throughout the body, Marfan syndrome can affect many systems, often causing abnormalities in the heart, blood vessels, eyes, bones, and joints. The two primary features of Marfan syndrome are vision problems caused by a dislocated lens (ectopia lentis) in one or both eyes and aortic root disease, leading to aneurysmal dilatation, aortic regurgitation and dissection is the main cause of morbidity and mortality in Marfan syndrome.

Prednisone is used for the treatment of myasthenia gravis if there is no initial response to the anticholinesterase medications. Pyridostigmine can make the symptoms of myasthenia gravis worse if used  in the initial stages of treatment. 

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.

Stridor is a sign of upper airway obstruction. One of the most common causes of stridor in children is laryngomalacia. In the absence of laryngomalacia, stridor presenting with respiratory distress, few chest signs and no preceding coryza symptoms or fever all point to the inhalation of a foreign object. This is common in children, with a peak incidence between 1 and 2 years of age. This child did not present with a high temperature, usually indicative of epiglottitis . The incidence of epiglottis has decreased due to the H. Influenza type b vaccine. Additionally viral croup and bronchiolitis present with upper respiratory tract infection. Asthma rarely presents with stridor but is rather associated with a wheeze.

Erythema nodosum is the most common type of inflammation of the subcutaneous fat tissue, referred to as panniculitis. Erythema nodosum appears as painful, erythematous round lumps, usually symmetrically on the anterior aspect of lower extremities. These lesions are self-limiting and tend to resolve within 2-8 weeks without undergoing necrosis. There are various causes of erythema nodosum, but the most important among children is the streptococcal throat infection. Other causes include autoimmune conditions like sarcoidosis, inflammatory bowel disease, mycobacterial infection (TB), and drugs like penicillin and sulphonamides. Coeliac disease is not linked with the formation of erythema nodosum.

Arterial blood gas is useful for the evaluation of oxygen and carbon dioxide gas exchange, respiratory function including hypoxia, and acid/base balance. This will quickly indicate if assisted ventilation is required for this patient.

Cyanotic congenital heart disease (CCHD) is a common cause of neonatal morbidity and mortality. They can be classified as CCHD due to:- Right-to-left shunt, associated with the decreased pulmonary flow, e.g., tetralogy of Fallot (TOF), pulmonary atresia, right-sided hypoplastic heart,- Right-to-left shunt, associated with the decreased aortic flow, e.g., left-sided hypoplastic heart, interrupted arch, severe coarctation| – Bidirectional shunt, e.g., TGA, DORV, TA, etc. Eisenmenger syndrome is not a neonatal CCHD| rather it develops later in young adulthood secondary to various CHD.

Based on the clinical scenario, the most probable diagnosis for this patient is maxillary sinusitis.The maxillary sinus drains from its superior aspect, leaving it prone to infections. It is the most commonly affected sinus in sinusitis.Common symptoms of maxillary sinusitis include postnasal discharge, pain, headache and toothache.Radiological imaging may show a fluid level in the antrum.Common organisms causing maxillary sinusitis include Haemophilus influenzae or Streptococcus pneumoniae.Treatment with antral lavage may facilitate diagnosis and relieve symptoms. Antimicrobial therapy has to be continued for long periods. Antrostomy may be needed.Other options:- Frontal sinusitis more commonly causes intracranial complications, but it is still less frequent than maxillary sinusitis.- The petrosal sinus is not a cavity within bone| rather, it is a venous structure located beneath the brain.- Frontoethmoidal sinusitis: It usually presents with frontal headache, nasal obstruction and altered sense of smell. Inflammation may progress to involve periorbital tissues. Ocular symptoms may occur, and secondary CNS involvement brought about by infection entering via emissary veins. CT scanning is the imaging modality of choice. Early cases may be managed with antibiotics. More severe cases usually require surgical drainage.

This child is experiencing delayed speech. By the age of 2, a child should be able to combine at least 2 words to make a very simple sentence.

Biliary atresia is a rare condition that usually becomes symptomatic 2 to 8 weeks after birth. It can be congenital or acquired. Typical symptoms include jaundice, weight loss, dark urine and pale stools.

The likely diagnosis in this case is Haemolytic Uremic Syndrome (HUS), which is generally seen in young children presenting with a triad of symptoms, namely: acute renal failure, microangiopathic haemolytic anaemia, and thrombocytopenia. The typical cause of HUS is ingestion of a strain of Escherichia coli. The laboratory results will usually include fragmented RBCs, decreased serum haptoglobin, reduced platelet count, nonspecific WBC changes, and normal coagulation tests (PTT included).

Liddle’s syndrome,  is an autosomal dominant disorder, that is characterized by early, and frequently severe, high blood pressure associated with low plasma renin activity, metabolic alkalosis, low blood potassium, and normal to low levels of aldosterone. Liddle syndrome involves abnormal kidney function, with excess reabsorption of sodium and loss of potassium from the renal tubule. Bartter Syndrome also presents with hypokalaemia, however blood pressure of these patients is usually low or normal.

According to the Rumack-Matthew Normogram, accurate levels of paracetamol can be measured only between 4-15 hours. The levels measured before 4 hours post-ingestion would highly underestimate the level of paracetamol ingested.The patient in question presents 2 hours after ingestion. Hence the most appropriate time to measure the levels of acetaminophen would be a further 2 hours later. Other options:- Note that the treatment with NAC can be delayed until the 4-hour level is obtained and compared to the nomogram.- Furthermore, haemodialysis is only indicated if she develops hepato-renal syndrome that is likely to occur 72-96 hours post-ingestion.- Indications for acute liver transplantation include persistent acidosis, hepatorenal syndrome and worsening coagulopathy.

When a child does not hear the sound in the middle during Weber test, it means they either they have a conductive hearing loss on the side they hear the sound, or a sensorineural hearing loss on the opposite side. Rinne’s test helps distinguish between the two. In this particular case, the hearing loss is most probably conductive due to the middle ear effusion. Therefore, Weber’s test should be localised to the left and Rinne’s should be positive on the right.

According to the Gell and Coombs classification of hypersensitivity reactions, the scenario provided is a type 4 (delayed) reaction.These reactions are mediated by T lymphocytes and cause contact dermatitis. Nickel, commonly found in cheap jewellery, is a common cause of contact dermatitis.Note:There are two main types of contact dermatitis:- Irritant contact dermatitis: It is a common, non-allergic reaction due to weak acids or alkalis (e.g. detergents). These are often seen on the hands. They present typically with erythema, and rarely, crusting and vesicles.- Allergic contact dermatitis: These are type IV hypersensitivity reactions and are often seen on the head following hair dyes.They typically present as acute weeping eczema which predominately affects the margins of the hairline rather than the hairy scalp itself. Treatment is usually with a potent topical steroid.Other options:- Allergic rhinitis is an example of a type 1 (immediate) reaction. It is an IgE mediated. It is a hypersensitivity to a previously innocuous substance.- Type 2 reactions are mediated by IgG and IgM, which binds to a cell, causing cell death. Goodpasture syndrome is an example of a type 2 hypersensitivity reaction.- Immune complexes mediate type 3 reactions. Rheumatoid arthritis is an example of a type 3 hypersensitivity reaction.

Time- 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 boy needs re-hydration due to his full thickness burn so IV fluids is the next most appropriate step. The greatest loss of plasma occurs in the first 12 hours after burn injury. The plasma loss then slowly decreases during the second 12 hours of the post-burn phase, although extensive leakage can continue for up to three days (Ahrns, 2004). Optimal fluid replacement during this period is essential to ensure cardiac output and renal and tissue perfusion. Usually, 36 hours post-burn, capillary permeability returns to normal and fluid is drawn back into the circulation. Burns of more than 15% of surface body area in adults and of over 10% in children warrant formal resuscitation.The Parkland formula for the total fluid requirement in 24 hours is as follows:4ml x TBSA (%) x body weight (kg)|50% given in first eight hours|50% given in next 16 hours.Children receive maintenance fluid in addition, at an hourly rate of:4ml/kg for the first 10kg of body weight plus|2ml/kg for the second 10kg of body weight plus|1ml/kg for >20kg of body weight.End pointUrine – adults: 0.5–1.0 ml/kg/hour|Urine – children: 1.0–1.5ml/kg/hour.

Oligohydramnios is a deficiency in the amniotic fluid volume, measured via ultrasound. Maternal factors associated with oligohydramnios include conditions where there is placental insufficiency such as chronic hypertension, preeclampsia or a thrombotic disorder, post-term pregnancy, premature rupture of membranes, certain chromosomal abnormalities, and obstructions of the foetal urinary tract. On the other hand conditions that are associated with polyhydramnios (excess amniotic fluid) include maternal diabetes, multiple gestations, Rh incompatibility and pulmonary abnormalities.

Lesch-Nyhan syndrome is a condition that occurs almost exclusively in males. This condition is inherited in an X-linked recessive pattern It is characterized by neurological and behavioural abnormalities and the overproduction of uric acid. Uric acid is a waste product of normal chemical processes and is found in blood and urine. Excess uric acid can be released from the blood and build up under the skin and cause gouty arthritis (arthritis caused by an accumulation of uric acid in the joints). Uric acid accumulation can also cause kidney and bladder stones.The nervous system and behavioural disturbances experienced by people with Lesch-Nyhan syndrome include abnormal involuntary muscle movements, such as tensing of various muscles (dystonia), jerking movements (chorea), and flailing of the limbs (ballismus). People with Lesch-Nyhan syndrome usually cannot walk, require assistance sitting, and generally use a wheelchair. Self-injury (including biting and head banging) is the most common and distinctive behavioural problem in individuals with Lesch-Nyhan syndrome.

Congenital heart diseases such as complete atrioventricular septal defects are most likely to cause large left to right shunts leading to faltering growth due to chronic severe hypoxia, pulmonary oedema, and feeding problems. Isolated atrial septal defects or ventricular septal defects result in relatively smaller shunts. Pulmonary stenosis and bicuspid aortic valve do not cause chronic systemic hypoxia. People with these conditions are often asymptomatic and only show some symptoms with intense physical activity.

Persistent pulmonary hypertension of the new-born is secondary to the failure of normal circulatory transition at birth, leading to an abnormally high pulmonary vascular resistance. This elevated resistance causes right-to-left shunting of blood and hypoxemia. It can be caused by parenchymal lung diseases (meconium aspiration syndrome, pneumonia or ARDS), lung hypoplasia (like occurring in oligohydramnios or diaphragmatic hernia), or it can be idiopathic. Other possible causes include maternal indomethacin use, group B streptococcal septicaemia, and high-pressure ventilation. Duct dependent congenital heart disease does not lead to persistent pulmonary hypertension.

Thyroglossal cyst is the most common congenital thyroid anomaly which is clinically significant and affects women more than men. It is a vestigial remnant of developing thyroid. Although the thyroglossal cyst can develop anywhere along the thyroglossal duct, the most common site is in the midline between the isthmus of thyroid and hyoid bone, or just above the hyoid. Thyroglossal cysts are also associated with ectopic thyroid tissue. Clinically, the cyst moves upward with protrusion of the tongue. Rarely, the persistent duct can become malignant (thyroglossal duct carcinoma) where the cancerous cells arise in the ectopic thyroid tissue that are deposited along the duct. Exposure to radiation is a predisposing factor.

Absence seizures are induced by over breathing or hyperventilation, while the other features suggest partial seizures.

The sinus venosus is a large quadrangular cavity which precedes the atrium on the venous side of the chordate heart. It exists distinctly only in the embryonic heart (where it is found between the two venae cavae)| however, the sinus venosus persists in the adult. In the adult, it is incorporated into the wall of the right atrium to form a smooth part called the sinus venarum, which is separated from the rest of the atrium by a ridge of fibres called the crista terminalis. The sinus venosus also forms the SA node and the coronary sinus.

A vasovagal episode or vasovagal syncope is the most common form of reflex syncope. Reflex syncope is a general term used to describe types of syncope resulting from a failure in autoregulation of blood pressure, and ultimately, in cerebral perfusion pressure resulting in transient loss of consciousness. The mechanisms responsible for this are complex and involve both depression of cardiac output as well as a decrease in vascular tone. Other types of reflex syncope include carotid sinus syncope and situational syncope, for instance, cough or micturition syncope. Vasovagal syncope may be triggered by pain or emotional upset, although frequently a specific trigger cannot be identified.

The most probable cause for chronic parotitis in this patient would be HIV infection.Rationale:Chronic infectious parotitis is relatively uncommon in children. While mycobacterial infection can result in chronic parotitis, HIV is a relatively more common cause. The presentation should always prompt an HIV test. Other options:- While mumps is the most common cause of acute viral parotitis, the chronic nature of the boy’s presentation rules it out. – Acute bacterial parotitis is usually unilateral and is warm and tender to touch.

Primitive reflexes are central nervous system responses, many of which disappear as a child matures. Retention of these reflexes may point to atypical neurology such as in cerebral palsy or stroke. However, some persist into adulthood. The stepping reflex is present from birth and normally disappears by 6 weeks, while the moro reflex is present from birth to about 4 months. The asymmetrical tonic neck reflex disappears by about 6 months. Reflexes that persist include the head righting reflex which develops at 6 months, and the parachute reflex which develops at 9 months.

According to the NICE guidelines, the frequency of stool passage is considered constipation when two or more of the following findings are present: Fewer than 3 stools a week, large hard stools, stools that resemble rabbit droppings| symptoms associated with defecation including distress, bleeding or straining| a history of previous episodes of a precious/current anal fissure. The child in the scenario fails to meet the criteria, and has no evidence of impacted faeces on examination. The best course of action is to encourage the parents to give the child more water to prevent dehydration, and feed the child a fibre rich diet including fruits, vegetables and high fibre bread.

Immunity against mumps develops over a long time. There is nothing to be done except to proceed with the usual vaccination schedule.