The most probable diagnosis for this patient is bilateral retractile testes. This a normal phenomenon in some pre-pubertal boys. Rationale:Testicular descent can continue until about 3-months of age. The pre-pubertal testis is small enough that with activation of the cremasteric reflex, they can enter the inguinal canal. This in itself is a normal finding providing the testis can be brought into the scrotum without tension and does not require surgical correction. With time the testis will lie within the scrotum. Orchidopexy for true undescended testis can be performed from 6-months of age. It is also warranted if the testes remain undescended or intra-abdominally leading to infertility.Other options:- An ascending testis is one, typically, following hernia or orchidopexy surgery that was in the testis but with time is within the inguinal canal and cannot be brought into the scrotum. Orchidopexy is required for this.- No surgery is required as when the testis enlarges with puberty it will remain within the scrotum.- The testes can be brought into the scrotum. Therefore they are not undescended.- The testes are retractile not ascending| ascending testis cannot be brought into the scrotum and would require orchidopexy.

All of the presenting features of the child are suggestive raised intracranial pressure. Thus, urgent treatment with 20% Mannitol can improve the child’s condition. Mannitol is an osmotic diuretic that is used in the treatment of raised intracranial pressure. It should be avoided in hypovolaemia because of its diuretic effects. Other options:- Head up at 15°: Keeping the head up at 20° in the midline will aid venous drainage. – Maintain CO2 at 5 kPa: If there is an acute rise in intracranial pressure, then lowering the CO2 to 4–4.5 kPa as a temporary measure can be beneficial. However, this must be only short-lived since it causes vasoconstriction and can impair cerebral blood flow. – 10% glucose bolus: Maintaining normoglycemia in traumatic brain injury is important. – 0.9% saline infusion: Hypertonic saline infusion of 3% can reduce intracranial pressure. 0.9% saline as a bolus could be beneficial if there were hypotension.

Drug withdrawal symptoms after a period of substance abuse can lead to a range of symptoms. Amphetamines are known to cause hypersomnia, hyperphagia, and irritability, as well as vivid dreams as a result of withdrawal. Similar symptoms are found in cocaine withdrawal. Alcohol withdrawal presents with symptoms such as insomnia, tremulousness and delirium. Ecstasy withdrawal includes irritation, mood swings, fatigue and insomnia. Heroin withdrawal presents with symptoms which include dilated pupils, insomnia, abdominal cramps and muscle aches. Withdrawal from prolonged cannabis use can cause depression, anxiety restlessness and insomnia.

The symptoms of excessive salivation and diarrhoea, along with hypotension, bradycardia, and bronchoconstriction, indicates excess parasympathetic nervous system activity. The patient is showing features of acetylcholine toxicity. Pesticides typically contain organophosphates that are potent inhibitors of acetylcholinesterase. This enzyme is responsible for the metabolism of acetylcholine. Acetylcholine is the neurotransmitter used in the neuromuscular junction, as well as at select points in the autonomic nervous system. The autonomic acetylcholine receptors can be nicotinic (more sensitive to nicotine) or muscarinic (more sensitive to muscarine). The most relevant receptors in this scenario are the muscarinic receptors as the majority are located in the parasympathetic nervous system smooth muscle, exocrine glands, and cardiac conduction system.Other options:- Accordingly, to cause the symptoms described, there must be an abundance of acetylcholine which stimulates the muscarinic receptors to enhance the parasympathetic effects. Therefore the reduction in the formation of acetylcholine option must be incorrect as this would produce the opposite effect. – Noradrenaline is the primary neurotransmitter in the sympathetic nervous system, and both answer options relating to noradrenaline would increase the neurotransmitter and potentiate the sympathetic nervous system effects, making them incorrect.Features can predict the accumulation of acetylcholine (mnemonic = SLUD):- Salivation- Lacrimation- Urination- Defecation/diarrhoeaCardiovascular symptoms include hypotension and bradycardia. The patient can show associated small pupils and muscle fasciculationManagement:- Atropine- The role of pralidoxime is still unclear – meta-analyses to date have failed to show any clear benefit.

Based on the given scenario, the most probable diagnosis for this patient is acquired immune deficiency syndrome (AIDS) caused by human immunodeficiency virus (HIV). Thus, the most appropriate investigation to confirm the underlying pathology in this patient would be viral serology. Rationale:The presence of oesophageal candidiasis is highly suggestive of severe immunosuppression. The causes of immunosuppression can be chemotherapy, with haematological malignancy, HIV or inhaled steroids. In patients with HIV, oesophageal candidiasis is part of the spectrum of AIDS-defining illnesses and usually occurs when the CD4 count is < 200 cells/microL. Other AIDS-defining illnesses include PCP pneumonia and CMV infections.Oesophageal Candidiasis:It is characterised by white spots in the oropharynx with extension into the oesophagus. It seldom occurs without an associated underlying risk factor like broad-spectrum antibiotic usage, immunosuppression and immunological disorders.Patients may present with oropharyngeal symptoms, odynophagia and dysphagia.Treatment is directed both at the underlying cause (which should be investigated for) and with oral antifungal agents.

The most probable diagnosis for this patient would be Edward syndrome.Edward syndrome results from trisomy 18. It is the second most common syndrome after Down syndrome. 60% of cases die within 48 hours, and 90% within the first year due to apnoeas. Cardiovascular abnormalities include atrial septal defect, ventricular septal defect and a persistent ductus arteriosus. There is no association with exophthalmos, but it may occur. Right choroid plexus cysts are found on coronal imaging, and 40–70% at post mortem are shown to have multiple large bilateral choroid plexus cysts (>10 mm). These may not become pathological but usually trigger an anomaly scan. Around 1% of cases may present with only a cyst, but 4% may present with other abnormalities.Other options:- Children with the velocardiofacial syndrome have a classic facial appearance with hypertelorism, a tubular nose, a cleft lip/palate abnormality and cardiac anomalies. – Children with Patau syndrome usually present with midline defects and are less likely to have rocker-bottom feet. – Children with Treacher Collins syndrome present with abnormalities of the branchial arches and pharyngeal pouches.

By 15 months, it’s common for many toddlers to:- say three to five words.- understand and follow simple commands.- point to one body part.- walk alone and begin to run.- climb on furniture.- make marks with a crayon.- imitate activities, such as housework.

External oblique forms the outermost muscle of the three muscles comprising the anterolateral aspect of the abdominal wall. Its aponeurosis comprises the anterior wall of the inguinal canal.

Factors V and VIII are consumed most rapidly in a patient with disseminated intravascular coagulation.Simultaneous coagulation and haemorrhage caused by initially formation of thrombi which consume clotting factors (factors 5,8) and platelets, ultimately leading to bleeding.Causes include:- Infection- Malignancy- Trauma e.g. major surgery, burns, shock, dissecting aortic aneurysm- Liver disease- Obstetric complicationsClinically bleeding is usually a dominant feature, bruising, ischaemia and organ failure.Blood tests reveal prolonged clotting times, thrombocytopenia, decreased fibrinogen and increased fibrinogen degradation products.Treatment of DIC involves treating the underlying cause and supportive management.Mnemonic:D-I-S-S-E-M-I-N-A-T-E-DD- D dimerI-Immune complexesS-Snakebite, shock, heatstrokeS-SLEE-Eclampsia, HELLP syndromeM-Massive tissue damageI-Infections: viral and bacterialN-NeoplasmsA-Acute promyelocytic leukaemiaT-Tumour products: Tissue Factor (TF) and TF-like factors released by carcinomas of pancreas, prostate, lung,colon, stomachE-Endotoxins (bacterial)D-Dead foetus (retained)

Mongolian spots, otherwise called congenital dermal melanocytosis, are pigmented birthmarks. They are usually located on the buttocks or back and although they’re usually present at birth, they may appear soon after. They are flat and have a blue-grey colour (bruise-like). They are benign and present no health risk.

The most probable diagnosis for this patient, according to the clinical scenario provided is tuberous sclerosis. It is an autosomal-dominant disorder characterised by hamartomas located throughout the body, often prominently involving the central nervous system and skin. Two loci on chromosomes 9 and 16 have been identified to be associated with this condition. The condition has a variable expression and penetrance and is further characterised by:- Seizures (usually infantile spasms)- Developmental delay- Facial/cutaneous angiofibromas (adenoma sebaceum)- Periungual fibromas (pink projections from the nail folds)- Shagreen patches (leathery thickenings of the skin usually on the back) – Ash leaf macules (areas of depigmentation that become visible under a Wood’s light)- Fundoscopy may reveal white streaks along the fundal vessels.

Umbilical vein catheterization utilizes the exposed umbilical stump in a neonate as a site for emergency central venous access up to 14 days old. Umbilical vein catheterization can provide a safe and effective route for intravenous delivery of medications and fluids during resuscitation.The indication for umbilical vein catheterization is when there is a need for IV access in a neonate for resuscitation, transfusions, or short-term venous access when otherwise unobtainable.

In haemophilia C, The severity of the deficiency is based on plasma factor XIC (clotting) activity. Major factor XI deficiency is present when the activity of factor XI in plasma is less than 1-15 IU/dL.In major deficiency factor XI, bleeding is related to injury, especially when trauma involves tissues rich in fibrinolytic activators, such as the oral mucosa, the nose, and the urinary tract. Unlike patients with severe haemophilia A or B, patients with major factor XI deficiency do not spontaneously bleed.The aPTT is usually prolonged in factor XI deficiency (but depends on the sensitivity of the reagent and test system–partial deficiency can be missed), whereas the PT and TT are normal.

With children nosebleeds often occur after nose picking and are benign in nature. For active bleeding, pressing of soft parts of the nose is required to stop the bleeding before doing anything else.

The nerve supply to the tensor tympani is the mandibular nerve.The mandibular nerve is the only division of the trigeminal nerve that carries motor fibres.Tensor tympani is a muscle that lies in a bony canal just superior to the pharyngotympanic tube. It originates from the cartilaginous portion of the pharyngotympanic tube, the bony canal in which it sits, and the greater wing of the sphenoid bone. It inserts into the upper part of the handle of the malleus. When contracted, it pulls the handle of the malleus medially. This action increases the tension across the tympanic membrane, reducing the magnitude of vibrations transmitted into the middle ear. This dampens loud noises or noises produced by chewing. Tensor tympani is innervated through the nerve to tensor tympani, which arises from the mandibular nerve.Other options:- The vestibulocochlear nerve is the eighth cranial nerve. This nerve has two components, a vestibular division that carries balance information, and a cochlear division that carries hearing information.- The glossopharyngeal nerve is the ninth cranial nerve. It has a wide range of functions. It carries taste and sensation from the posterior third of the tongue, as well as sensation from the pharyngeal wall and tonsils, the middle ear, external auditory canal and auricle. It carries parasympathetic fibres that supply the parotid gland. It also supplies the baroreceptors and chemoreceptors of the carotid sinus and supplies the secretomotor fibres to the parotid gland.- The maxillary nerve carries only sensory fibres.- The facial nerve is the seventh cranial nerve. It supplies the muscles of facial expression, as well as stylohyoid, the posterior belly of digastric, and stapedius (the only other muscle associated with the middle ear). It carries taste from the anterior two-thirds of the tongue and sensation from part of the external acoustic meatus, parts of the auricle and the retro-auricular area. It provides secretomotor fibres which supply to the submandibular gland, sublingual gland (via chorda tympani nerve), nasal glands and lacrimal glands.

This temperature is considered to be a mild fever and is most often caused by a minor infection in children of this age. Therefore, an infection screen should be conducted and an IV antibiotic.

Treating persons infected with C. trachomatis prevents adverse reproductive health complications and continued sexual transmission, and treating their sex partners can prevent reinfection and infection of other partners. Treating pregnant women usually prevents transmission of C. trachomatis to neonates during birth. Chlamydia treatment should be provided promptly for all persons testing positive for infection. Treatment delays have been associated with complications (e.g. PID) in a limited proportion of women. To minimise disease transmission to sex partners, persons treated for chlamydia should be instructed to abstain from sexual intercourse for 7 days after single-dose therapy or until completion of a 7-day regimen and resolution of symptoms if present. To minimise risk for reinfection, patients also should be instructed to abstain from sexual intercourse until all of their sex partners are treated. Persons who receive a diagnosis of chlamydia should be tested for HIV, GC, and syphilis.

The Five P’s: pain, pulselessness, paraesthesia, paralysis, and pallor, are the most common symptoms of compartment syndrome. However, late signs of the condition include the absence of distal pulses.

Consuming iron in its Fe2+ (ferrous form) form can improve the ability to absorb dietary iron in patients with iron deficiency anaemia (IDA). Clinical features of IDA include:- Koilonychia- Atrophic glossitis- Post-cricoid webs- Angular stomatitisThe peripheral blood smear shows the following abnormal RBC morphologies:- Target cells- Pencil poikilocytes- Microcytic-hypochromic cells

The lingual nerve wraps around Wharton’s duct, and thus, is at risk of injury as the submandibular gland is mobilised. The lingual nerve provides sensory supply to the anterior 2/3 of the tongue.Note:- Submandibular duct (Wharton’s duct): It opens lateral to the lingual frenulum on the anterior floor of the mouth. It is around 5 cm in length.- Lingual nerve wraps around Wharton’s duct. As the duct passes forwards, it crosses medial to the nerve, above it and then crosses back, lateral to it, to reach a position below the nerve.

Precocious puberty is the attainment of normal pubertal biochemical and physical features at an abnormally earlier age. The age cut-offs commonly used to define precocious puberty are 8 years for females and 9 years for males. The onset of normal puberty is triggered by gonadotropic-releasing hormones from the hypothalamus.In most of the familial cases, the condition is transmitted by affected father. In boys, this makes up about 5% of the cases.Full adult height potential is not achieved in patients of precious puberty, although there is an advanced bone maturation.

Among the options provided, zidovudine causes lipoatrophy as a side effect.Zidovudine: Although both hypertrophy and atrophy are described related to HIV medications, nucleoside reverse transcriptase inhibitor (NRTIs) such as zidovudine and stavudine are closely associated with fat loss.Other options:- Enfuvirtide is an HIV-fusion inhibitor. Lipoatrophy is not commonly associated with this drug.- Efavirenz is an NNRTI, which is not associated with lipoatrophy. Common side effects include neuropsychiatric effects, rash and nausea. – Ganciclovir is not an anti-HIV medication and is used for cytomegalovirus (CMV) infections.- Raltegravir is an integrase inhibitor and is associated with fat gain.

Syphilis is an infectious venereal disease caused by the spirochete Treponema pallidum. Syphilis is transmissible by sexual contact with infectious lesions, from mother to foetus in utero, via blood product transfusion, and occasionally through breaks in the skin that come into contact with infectious lesions. If untreated, it progresses through 4 stages: primary, secondary, latent, and tertiary. Primary and secondary syphilis are easy to treat with a penicillin injection. Penicillin is one of the most widely used antibiotics and is usually effective in treating syphilis. People who are allergic to penicillin will likely be treated with a different antibiotic, such as:doxycyclineazithromycinceftriaxone

Constipation is often associated with nocturnal enuresis in children. The palpable mass is the impacted stool. The decreased appetite is common in those with constipation.

Answer: Cystine stoneCystinuria is a genetic cause of kidney stones with an average prevalence of 1 in 7000 births. Cystine stones are found in 1 to 2 percent of stone formers, although they represent a higher percentage of stones in children (approximately 5 percent). Cystinuria is an inherited disorder. Inherited means it is passed down from parents to children through a defect in a specific gene. In order to have cystinuria, a person must inherit the gene from both parents. Cystine is a homodimer of the amino acid cysteine. Patients with cystinuria have impairment of renal cystine transport, with decreased proximal tubular reabsorption of filtered cystine resulting in increased urinary cystine excretion and cystine nephrolithiasis. The cystine transporter also promotes the reabsorption of dibasic amino acids, including ornithine, arginine, and lysine, but these compounds are soluble so that an increase in their urinary excretion does not lead to stones. Intestinal cystine transport is also diminished, but the result is of uncertain clinical significance.Cystinuria only causes symptoms if you have a stone. Kidney stones can be as small as a grain of sand. Others can become as large as a pebble or even a golf ball. Symptoms may include:Pain while urinatingBlood in the urineSharp pain in the side or the back (almost always on one side)Pain near the groin, pelvis, or abdomenNausea and vomitingStruvite stones are a type of hard mineral deposit that can form in your kidneys. Stones form when minerals like calcium and phosphate crystallize inside your kidneys and stick together. Struvite is a mineral that’s produced by bacteria in your urinary tract. Bacteria in your urinary tract produce struvite when they break down the waste product urea into ammonia. For struvite to be produced, your urine needs to be alkaline. Having a urinary tract infection can make your urine alkaline. Struvite stones often form in women who have a urinary tract infection.Calcium oxalate stones are the most common type of kidney stone. Kidney stones are solid masses that form in the kidney when there are high levels of calcium, oxalate, cystine, or phosphate and too little liquid. There are different types of kidney stones. Your healthcare provider can test your stones to find what type you have. Calcium oxalate stones are caused by too much oxalate in the urine.What is oxalate and how does it form stones?Oxalate is a natural substance found in many foods. Your body uses food for energy. After your body uses what it needs, waste products travel through the bloodstream to the kidneys and are removed through urine. Urine has various wastes in it. If there is too much waste in too little liquid, crystals can begin to form. These crystals may stick together and form a solid mass (a kidney stone). Oxalate is one type of substance that can form crystals in the urine. This can happen if there is too much oxalate, too little liquid, and the oxalate “sticks” to calcium while urine is being made by the kidneys.Uric acid stones are the most common cause of radiolucent kidney stones in children. Several products of purine metabolism are relatively insoluble and can precipitate when urinary pH is low. These include 2- or 8-dihydroxyadenine, adenine, xanthine, and uric acid. The crystals of uric acid may initiate calcium oxalate precipitation in metastable urine concentrates.Uric acid stones form when the levels of uric acid in the urine is too high, and/or the urine is too acidic (pH level below 5.5) on a regular basis. High acidity in urine is linked to the following causes:Uric acid can result from a diet high in purines, which are found especially in animal proteins such as beef, poultry, pork, eggs, and fish. The highest levels of purines are found in organ meats, such as liver and fish. Eating large amounts of animal proteins can cause uric acid to build up in the urine. The uric acid can settle and form a stone by itself or in combination with calcium. It is important to note that a person’s diet alone is not the cause of uric acid stones. Other people might eat the same diet and not have any problems because they are not prone to developing uric acid stones.There is an increased risk of uric acid stones in those who are obese or diabetic.Patients on chemotherapy are prone to developing uric acid stones.Only cystine stone is inherited.

A minority of affected individuals may experience severe liver failure. This happens most frequently in people with Wilson’s disease during adolescence and more commonly in women. These individuals may rapidly develop signs and symptoms of liver disease, often associated with anaemia due to breakdown of red blood cells (haemolysis) and mental confusion. In some patients, liver disease does not reveal itself, and the patient develops neurologic (brain-related) symptoms. Common neurological symptoms of Wilson disease that may appear and progress with time include tremor, involuntary movements, difficulty swallowing (dysphagia), difficulty speaking and poor articulation (dysarthria), lack of coordination, spasticity, dystonic postures, and muscle rigidity. Almost all affected individuals with the neurological symptoms of Wilson’s disease have Kayser-Fleischer rings in their eyes that can be identified by a slit lamp examination.

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

The patient’s sugar levels typically show the Dawn phenomenon.Dawn phenomenon:This is an early morning rise in blood glucose levels secondary to a rise in hormones that increase blood glucose levels. The question suggests that he is undergoing a pubertal growth spurt, suggesting that an increase in these hormones is what has led to the higher morning glucose levels.Other options:- Inactivity at night-time: It is expected, and insulin dose should be adequate despite inactivity during the night.- Inadequate bedtime insulin: It is possible that this is a contributing factor. However, inadequate background insulin is also likely to result in high blood glucose in the day, which the question does not suggest.- Somogyi effect: There are no features suggestive of nocturnal hypoglycaemia that can cause the Somogyi effect.- Nocturnal glycogenesis: Glycogenesis would result in hypoglycaemia, not hyperglycaemia.

Based on the clinical scenario, the most likely underlying pathogen is the Epstein Barr virus (EBV).An Epstein Barr virus (EBV) infection most commonly results in upper respiratory tract symptoms with fever and sore throat. Lymphadenopathy is frequently palpable on examination. Splenomegaly may also occur, and for this reason, patients diagnosed with glandular fever should be advised to avoid contact sports for one month following diagnosis. The presence of petechiae on the soft palate is also associated with EBV infection. The vast majority of patients with active EBV infection will develop a widespread rash if given amoxicillin, therefore, phenoxymethylpenicillin (Penicillin V) is recommended for the treatment of a suspected bacterial throat infection to prevent this complication occurring for individuals who have EBV infection.Other options:- Coronavirus: This is one of the causes of the common cold and is frequently responsible for sore throats| however, in this case, the presenting features are more suggestive of an EBV infection.- Group A Streptococcus: Streptococci are classified into two main groups| alpha-haemolytic and beta-haemolytic. Group A Streptococcus belongs to the beta-haemolytic group. Group A streptococcal infection is a common cause of bacterial tonsillitis. It is possible that the child, in this case, had streptococcal tonsillitis and has had a drug reaction to the amoxicillin. However her age, flu-like symptoms and petechiae on her palate all point to an EBV infection and amoxicillin resulting in a rash.- Parainfluenza: Parainfluenza viruses are one of many causes of the common cold and can cause pharyngitis. They are the leading cause of viral croup.- Rhinovirus: Rhinoviruses are one of many causes of the common cold and are frequently responsible for sore throats| however, in this case, are other factors suggesting EBV infection.

Bilious (green) gastric aspirate or emesis indicates that the intestines are obstructed below the ampulla of Vater.Gastrointestinal (GI) endoscopy is actually considered an essential diagnostic and therapeutic technique. Upper GI endoscopy in neonatal age allows for exploration of the oesophagus, stomach and duodenum| instead lower GI endoscopy easily reaches the sigmoid-colon junction.