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.

Achondroplasia is one of the commonest forms of skeletal dysplasias that lead to dwarfism. Multiple skeletal deformities are associated with it but the common cranial abnormalities are macrocephaly, frontal bossing, depressed nasal bridge, narrowed foramen magnum, and the presence of communicating hydrocephalus. A prominent maxilla is not associated with achondroplasia.

The T wave represents ventricular repolarization. Other options:- P wave:Depolarization that spreads from the SA node throughout the atria. The wave lasts 0.08 to 0.1 seconds (80-100 ms).The isoelectric period after the P wave represents the time in which the impulse is travelling within the AV node.- P-R interval:Time from the onset of the P wave to the beginning of the QRS complex. The wave ranges from 0.12 to 0.20 seconds in duration.Represents the time between the onset of atrial depolarization and the onset of ventricular depolarization- QRS complex:It represents ventricular depolarization. The duration of the QRS complex is normally 0.06 to 0.1 seconds.- ST-segment:The isoelectric period following the QRS. It represents the period in which the entire ventricle is depolarized and roughly corresponds to the plateau phase of the ventricular action potential- U wave: It is a small positive wave which may follow the T wave. It represents the last remnants of ventricular repolarization.- Q-T intervalIt represents the time for both ventricular depolarization and repolarization to occur, and therefore roughly estimates the duration of an average ventricular action potential.The interval ranges from 0.2 to 0.4 seconds depending upon heart rate.At high heart rates, ventricular action potentials shorten in duration, which decreases the Q-T interval. Therefore the Q-T interval is expressed as a corrected Q-T (QTc) by taking the Q-T interval and dividing it by the square root of the R-R interval (interval between ventricular depolarizations). This allows an assessment of the Q-T interval that is independent of heart rate.The normal corrected Q-Tc interval is less than 0.44 seconds.

The correct answer is triple X syndrome with a genotype of XXX and an almost normal female phenotype. The extra X chromosome is inactive. The final phenotype of an individual is determined after normal sexual and gonadal differentiation, a process that involves several genes located on chromosomes X and Y. Disorders of sexual differentiation result in cases of ambiguous genitalia and are caused by a number of genetic abnormalities. Among these disorders is the turner syndrome with a genotype of 45X0, characterized by gonadal dysgenesis and ovarian failure. DAX-1 gene mutation leads to congenital adrenal hypoplasia and hypogonadotropic hypogonadism, which results in virilization of female external genitalia. Campomelic dysplasia results from mutation of the SOX-9 gene, leading to 46XY sex reversal. Danys-Drash syndrome is characterized by disordered sexual development in affected males due to the mutated WT-1 gene, which also causes Wilm’s tumour.

Answer: Surveillance annual flexible sigmoidoscopy from age 13 years until age 30 years. Familial adenomatous polyposis (FAP) is the most common adenomatous polyposis syndrome. It is an autosomal dominant inherited disorder characterized by the early onset of hundreds to thousands of adenomatous polyps throughout the colon. If left untreated, all patients with this syndrome will develop colon cancer by age 35-40 years. In addition, an increased risk exists for the development of other malignancies.Most patients with FAP are asymptomatic until they develop cancer. As a result, diagnosing presymptomatic patients is essential.Of patients with FAP, 75%-80% have a family history of polyps and/or colorectal cancer at age 40 years or younger.Nonspecific symptoms, such as unexplained rectal bleeding (haematochezia), diarrhoea, or abdominal pain, in young patients may be suggestive of FAP.In a minority of FAP families a mutation cannot be identified and so annual flexible sigmoidoscopy should be offered to at risk family members from age 13–15 years until age 30, and at three to five year intervals thereafter until age 60 years.

Developmental dysplasia of the hip (DDH) is a spectrum of anatomical abnormalities of the hip joint in which the femoral head has an abnormal relationship with the acetabulum.Plain radiographs are of limited value for diagnosis in the new-born child because the femoral head and acetabulum are largely cartilaginous. Ultrasound scanning is the investigation of choice to evaluate DDH in infants younger than six months of age and is useful to diagnose more subtle forms of the disorder when a clinical exam is equivocal. It is also the only imaging modality that enables a three-dimensional real-time image of a neonate’s hip.

Because of the patient’s history of chronic analgesic use of daily paracetamol intake, the most likely diagnosis of this case is Analgesic misuse headache. In these cases, the headache is only temporarily relieved by analgesics. Treatment involves gradual withdrawal of analgesics.

A written protocol is important in clinical research as it helps to decrease bias with early findings as the process of the trial has been documented in advance. To show that the study has been properly undertaken before commencing, the investigators must document their names| they must describe the process, detail the analysis that will be undertaken, and provide a power calculation. The ethics committee does not always need to see the protocol.

The most prudent course of action in the given clinical scenario is an ovary-sparing cystectomy. The history is 3-months and is already chronic. Furthermore, the cyst is greater than 5cm in size and at risk of torsion. This will relieve the cause of pain, reduce the risk of torsion and save ovarian function.Other options:- This is a simple cyst and not a malignancy, so imaging and referral are not indicated.- Open oophorectomy was done in the past. However, this is very aggressive, and the modern approach is ovary-sparing.- As the cyst is 7cm and at risk of torsion, conservative management is not appropriate.

The most appropriate next step in the management would be to refer the patient for an ENT opinion. Rationale:This child has clinical signs of adenotonsillar hypertrophy, symptoms of persistent snoring and features of obstructive sleep apnoea (OSA). Suspected OSA warrants referral to an ENT specialist. Other options:- Capillary blood gas: The investigation consists of overnight oxygen saturation monitoring or polysomnography.- Chest X-ray: A chest x-ray is not indicated.- Phenoxymethylpenicillin (Penicillin V) is the first-line treatment for tonsillitis. However, with a history of several months and no suggestion of fever or sore throat, acute tonsillitis is unlikely.- Weight loss advice: Obesity is a risk factor for obstructive sleep apnoea (OSA) amongst other health problems. The child’s weight should be highlighted and advice and support for weight loss provided however referral to ENT is warranted for further investigation.

Reed-Sternberg cells are classically associated with Hodgkin lymphoma.Classical diagnostic Reed-Sternberg cells are large (15 to 45 micrometres), have abundant slightly basophilic or amphophilic cytoplasm and have at least two nuclear lobes or nuclei. Diagnostic Reed-Sternberg cells must have at least two nucleoli in two separate nuclear lobes. The nuclei are large and often rounded in contour with a prominent, often irregular nuclear membrane, pale chromatin and usually one prominent eosinophilic nucleolus, with perinuclear clearing (halo), resembling a viral inclusion.

Among the options provided, an 8-week-old full-term infant with normal developmental milestones will smile in response to appropriate stimuli.Rationale:Smiles in response to appropriate stimuli are seen from around 6 weeks of age. A social smile, where the infant has an awareness that a smile attracts attention, is not observed until around 3 months of age.Other options:- At 6 weeks an infant is able to follow objects in the horizontal plane through 90 deg| fixing and following an object through 180 deg in the horizontal plane is a milestone achieved at 3 months, as is pushing up onto forearms. – Pushing up onto hands occurs by around 5 months.- Infants of 3 months should startle to a 60 dB sound.

Marfan syndrome (MFS) is a spectrum of disorders caused by a heritable genetic defect of connective tissue that has an autosomal dominant mode of transmission. The defect itself has been isolated to the FBN1 gene on chromosome 15, which codes for the connective tissue protein fibrillin. Abnormalities in this protein cause a myriad of distinct clinical problems, of which the musculoskeletal, cardiac, and ocular system problems predominate.The most severe of these clinical problems include aortic root dilatation and dissection, which have historically been the causative factors in early patient demise. Skeletal deformities such as thoracolumbar scoliosis, thoracic lordosis, and pectus excavatum, may lead to pulmonary difficulties that include restrictive airway disease and cor pulmonale if the deformities are progressive and untreated. Finally, blindness may result from unrecognized and untreated glaucoma, retinal detachment, and cataracts.The skeleton of patients with MFS typically displays multiple deformities including arachnodactyly (i.e., abnormally long and thin digits), dolichostenomelia (i.e., long limbs relative to trunk length), pectus deformities (i.e., pectus excavatum and pectus carinatum), and thoracolumbar scoliosis. In the cardiovascular system, aortic dilatation, aortic regurgitation, and aneurysms are the most worrisome clinical findings. Mitral valve prolapse that requires valve replacement can occur as well. Ocular findings include myopia, cataracts, retinal detachment, and superior dislocation of the lens.Other features:General tall staturePectus excavatum or carinatumDisproportionately long, slender armsDisproportionately long digitsArachnodactylyFinger contracturesReduced extension of elbows (< 170 degrees)Protrusio acetabuli (intrapelvic displacement of the acetabulum)Pes planus (flat feet)HypermobilityArthralgiaJoint instabilityScoliosisKyphosisDolichocephalia (elongated face)High arched palateDental crowdingDental malocclusion

Erb’s palsy is a paralysis of the arm caused by injury to the brachial plexus, specifically the severing of the upper trunk C5–C6 nerves.The infant with an upper plexus palsy (C5-C7) keeps the arm adducted and internally rotated, with the elbow extended, the forearm pronated, the wrist flexed, and the hand in a fist. In the first hours of life, the hand also may appear flaccid, but strength returns over days to months.The right side is injured in 51% of cases. Left side occurs in 45% of patients and bilateral injuries, in 4%.

Milestones of 3 years old:Social and Emotional:Copies adults and friends Shows affection for friends without prompting Takes turns in games Shows concern for crying friend Understands the idea of “mine” and “his” or “hers” Shows a wide range of emotions Separates easily from mom and dad May get upset with major changes in routineDresses and undresses self Language/Communication:Follows instructions with 2 or 3 steps Can name most familiar things Understands words like “in,” “on,” and “under” Says first name, age, and sexNames a friend Says words like “I,” “me,” “we,” and “you” and some plurals (cars, dogs, cats) Talks well enough for strangers to understand most of the time Carries on a conversation using 2 to 3 sentences Cognitive (learning, thinking, problem-solving):Can work toys with buttons, levers, and moving parts Plays make-believe with dolls, animals, and people Does puzzles with 3 or 4 pieces Understands what “two” means Copies a circle with pencil or crayon Turns book pages one at a time Builds towers of more than 6 blocks Screws and unscrews jar lids or turns door handle Movement/Physical Development:Climbs well Runs easily Pedals a tricycle (3-wheel bike) Walks up and down stairs, one foot on each step

Scurvy is a condition caused by a dietary deficiency of vitamin C, also known as ascorbic acid. Humans are unable to synthesize vitamin C, therefore the quantity of it that the body needs has to come from the diet. The presence of an adequate quantity of vitamin C is required for normal collagen synthesis. In scurvy bleeding tendency is due to capillary fragility and not coagulation defects, therefore blood tests are normal.

The boy has an increased BMI which implies he is overweight. Possible trauma to his pancreas might have led to a diabetes-like condition, induced by damage to the beta cells. Fasting blood glucose should be measured as a follow-up strategy to see if the damage is reversible or irreversible and to conclude if the glycosuria is related to his metabolic profile or to his accident.

The given presentation is highly suggestive of withdrawal effect of ketamine.Ketamine is known for its unique property of inducing dissociative anaesthesia. Emergence phenomenon (as seen in the child in question) is an adverse effect that occurs during recovery from dissociative anaesthesia. The components of emergence phenomenon include a euphoric state associated with hallucinations.

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.

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.

Adrenal insufficiency is a serious medical condition that leads to inadequate secretion of corticosteroids. The consequences of this deficiency are numerous electrolyte and acid-base imbalances, which include hyponatremia, hyperkalaemia, hypercalcemia, hypoglycaemia, metabolic alkalosis, and dehydration.

Duchenne muscular dystrophy has an X-linked recessive pattern of inheritance. Since the first son is affected by the disease, it means that the mother is a carrier. The male children will inherit the Y chromosome from their father and the X chromosome from their mother, having 50% chances of inheriting the X chromosome with the affected gene.

Chickenpox is a highly communicable viral disease caused by human (alpha) herpesvirus 3 (varicella-zoster virus, VZV). It is transmitted from person to person by direct contact (touching the rash), droplet or air born spread (coughing and sneezing).

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.

Capillary haemangiomas (strawberry naevi) are very common benign tumours that may appear in infancy. This particular case requires a close follow-up to monitor the naevus’ size and make sure it doesn’t expand or gets bigger, affecting the baby’s visual field.It is more common in preterm babies and girls are 3x more commonly affected than boys. It presents at birth in 30%, and is a focal and solitary in 80% of cases, most commonly found on the head and neck (60%), followed by the trunk (25%) and extremities (15%).

Prader-Willi Syndrome is a genetic disorder that occurs when a chromosome from paternal chromosome 15q is deleted or unexpressed during the formation of the egg or sperm, or in embryonic development. Individuals usually inherit one copy of this gene from each parent, and in this case on the paternal gene remains active in parts of the brain and other organs. This phenomenon is known as genetic imprinting, and is also seen in Angelman’s syndrome. Symptoms seen in Prader-Willi range from poor muscle tone during infancy to developmental and cognitive delays. Many individuals suffer from hypogonadism that affects fertility in both males and females. In Angelman’s syndrome the maternal chromosome 15q is unexpressed. The condition is also called happy puppet syndrome as affected children present with a happy demeanour, ataxic gait, and flapping movements of the limbs.

When a child with joint problems presents with red-eye, the likelihood of anterior uveitis must be excluded by involving an ophthalmologist in the assessment. This is because uveitis is the most common extra-articular manifestation of juvenile idiopathic arthritis.Other options:- Cataract: It does not give rise to a red-eye, but leukocoria. Often this would have been picked up at an earlier age. – A patient with a corneal foreign body almost would almost invariably give a suspicious history (onset while playing outdoors etc.), as well as have marked symptoms of ocular discomfort (red, watery and painful eyes). – A child with periorbital cellulitis often presents acutely unwell and distressed. – A child with an uncorrected refractive error often complains of being unable to see in class and does not normally present with ocular redness.

Given the presentation of short stature, primary amenorrhea, puffy arms, and a webbed neck in a 5-year-old girl, the most likely diagnosis is: Turner’s syndrome

Reasoning:

• Short Stature: Common in Turner syndrome.
• Primary Amenorrhea: Typical in Turner syndrome due to ovarian dysgenesis.
• Puffy Arms: Lymphedema is common in Turner syndrome, particularly in infancy.
• Webbed Neck: A classic feature of Turner syndrome.

Other Conditions:

• Down’s Syndrome: Typically presents with intellectual disability, characteristic facial features, and sometimes congenital heart defects, but not usually with primary amenorrhea or a webbed neck.
• Klinefelter’s Syndrome: Affects males and presents with hypogonadism and infertility, not applicable to a 5-year-old girl.
• Fragile X Syndrome: Primarily presents with intellectual disability and physical features such as an elongated face and large ears, not with a webbed neck or amenorrhea.

CF is inherited in an autosomal recessive manner.This means that to have CF, a person must have a mutation in both copies of the CFTR gene in each cell. People with CF inherit one mutated copy of the gene from each parent, who is referred to as a carrier.CF carriers can pass their copy of the CFTR gene mutation to their children. Each time two CF carriers have a child together, the chances are: 25 percent (1 in 4) the child will have CF50 percent (1 in 2) the child will be a carrier but will not have CF25 percent (1 in 4) the child will not be a carrier of the gene and will not have CFThis male’s parents are obligate carrier because he has a sibling with CFSo the chances he is a carrier too are 2 in 3The risk of having an affected child is the chance of both himself and his partner being carriers: (2/3 × 1/25 = 2/75) × 1/4 = 1/150.

The Chi-squared test evaluates if two variables are related. The other statistical tests mentioned do not perform this function.