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Question 1
Correct
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A 15 month old boy has a history of repeated bacterial pneumonia, failure to thrive and a sputum culture positive for H.influenzea and S.pneumoniae. There is no history of congenital anomalies. He is most likely suffering from?
Your Answer: X-linked agammaglobulinemia
Explanation: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. -
This question is part of the following fields:
- Respiratory
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Question 2
Correct
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What proportion of salivary secretions is contributed by the submandibular glands?
Your Answer: 0.7
Explanation:The submandibular glands provide the bulk of salivary secretions contributing close to 70%. The sublingual glands provide 5% and the remainder from the parotid.
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This question is part of the following fields:
- ENT
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Question 3
Correct
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As the junior doctor on duty you are called to see a 4 year old boy who is has been experiencing intermittent temperature spikes of 38.7C throughout the night. He underwent a laparoscopic appendicectomy for a perforated appendix four days ago, and has opened his bowels with diarrhoea. His chest is clear on examination.Which of the following is the most likely explanation for his condition?
Your Answer: Intra-abdominal collection
Explanation:Perforated appendices are common in children as it is more difficult to surgically assess an unwell child due to poor localisation of abdominal pain, and their inability to express discomfort. They are therefore prone to a greater risk of post operative complications including would infections, intra abdominal fluid collections, and chest infections. In the above scenario the spiking temperature points to an abscess, which characteristically presents with a swinging temperature. The fever is unlikely due to bacterial resistance as blood tests performed post surgery would have indicated any resistance, and a UTI is also unlikely since the child is already on antibiotics. As his chest is clinically clear, a severe chest infection may be ruled out, leaving intra-abdominal collection as the most likely explanation.
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This question is part of the following fields:
- Paediatric Surgery
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Question 4
Incorrect
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Which of the following conditions is usually inherited in an autosomal dominant fashion?
Your Answer: Friedreich's ataxia
Correct Answer: Familial adenomatous polyposis
Explanation:Familial adenomatous polyposis can have different inheritance patterns.When familial adenomatous polyposis results from mutations in the APC gene, it is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition.When familial adenomatous polyposis results from mutations in the MUTYH gene, it is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition.
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This question is part of the following fields:
- Genetics And Dysmorphology
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Question 5
Incorrect
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Which of the following maternal factors is associated with oligohydramnios?
Your Answer: Polycystic kidney disease
Correct Answer: Maternal thrombotic disorder
Explanation: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.
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This question is part of the following fields:
- Neonatology
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Question 6
Correct
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Which of the following cell types makes a significant contribution to the blood brain barrier?
Your Answer: Astrocyte
Explanation:The blood-brain barrier (BBB) is a term used to describe the unique properties of the microvasculature of the central nervous system (CNS). CNS vessels are continuous nonfenestrated vessels, but also contain a series of additional properties that allow them to tightly regulate the movement of molecules, ions, and cells between the blood and the CNS.Blood vessels are made up of two main cell types: Endothelial Cells (ECs) that form the walls of the blood vessels, and mural cells that sit on the abluminal surface of the EC layer. The properties of the BBB are largely manifested within the ECs, but are induced and maintained by critical interactions with mural cells, immune cells, glial cells, and neural cells, which interact in the neurovascular unit.Astrocytes are a major glial cell type, which extends polarized cellular processes that ensheath either neuronal processes or blood vessels.This includes regulating the contraction/dilation of vascular smooth muscle cells surrounding arterioles as well as PCs surrounding capillaries. Astrocytes have been identified as important mediators of BBB formation and function because of the ability of purified astrocytes to induce barrier properties.
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This question is part of the following fields:
- Neurology And Neurodisability
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Question 7
Correct
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A 4-year-old girl with an abnormal facial appearance has an ejection systolic murmur radiating to between her scapulae. A radio-femoral delay was also found. Which of the following is the most probable cause?
Your Answer: Turner's syndrome
Explanation:These cardiovascular findings are suggestive of coarctation of the aorta, which is common among patients with Turner’s syndrome. Physical features of Turner’s syndrome include a short neck with a webbed appearance, a low hairline at the back of the head, low-set ears, and narrow fingernails and toenails that are turned upward.Atrioventricular septal defect is the most common cardiac anomaly in Down’s syndrome. Structural heart defects at birth (i.e., ventricular septal defect, atrial septal defect, patent ductus arteriosus) are common in Edward’s syndrome. Pulmonary stenosis with or without dysplastic pulmonary valve and hypertrophic cardiomyopathy are common in Noonan’s syndrome. Supravalvar aortic stenosis and peripheral pulmonary stenosis are found in William’s syndrome.
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This question is part of the following fields:
- Genetics And Dysmorphology
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Question 8
Correct
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Which of the following developmental milestones is a 3 year old girl unlikely to have achieved?
Your Answer: Make good cuts with scissors
Explanation:At the age of three years a child is to be able to dress and undress himself with supervision, eat with a spoon and fork, build a tower with 9 cubes, give their full name and copy a circle. The child will not be able to make good cuts with scissions until he is about 5 years old.
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This question is part of the following fields:
- Child Development
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Question 9
Correct
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A 16-year-old boy presents to the physician with a history of easy bruising and epistaxis since childhood. He recently had a dental extraction after which the bleeding lasted for 30 hours. His labs are sent and the reports are as follows: APTT: 36 secondsPT: 15 secondsFibrinogen: 2.5 g/lFactor VIIIC: 0.4 iu/ml (normal range 0.5-1.5)vWF antigen: 0.35 iu/ml (normal range 0.45-1.4)vWF ristocetin co-factor: 0.05 iu/ml (normal 0.45-1.35)PLT: 230 x 109/lBleeding time: 12 mins (normally up to 8 mins). Which of the following is the most likely diagnosis?
Your Answer: von Willebrand disease type II
Explanation:Von Willebrand disease (VWD), a congenital bleeding disorder caused by deficient or defective plasma von Willebrand factor (VWF), may only become apparent on haemostatic challenge, and bleeding history may become more apparent with increasing age. Type 1 VWD (,30% of VWD) typically manifests as mild mucocutaneous bleeding. Type 2 VWD accounts for approximately 60% of VWD. Type 2 subtypes include: Type 2A, which usually manifests as mild-to-moderate mucocutaneous bleeding| Type 2B, which typically manifests as mild-to-moderate mucocutaneous bleeding that can include thrombocytopenia that worsens in certain circumstances| Type 2M, which typically manifests as mild-moderate mucocutaneous bleeding| Type 2N, which can manifest as excessive bleeding with surgery and mimics mild haemophilia A. Type 3 VWD (<10% of VWD) manifests with severe mucocutaneous and musculoskeletal bleeding.
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This question is part of the following fields:
- Haematology And Oncology
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Question 10
Correct
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A 15-year-old boy was brought by his mother due to his recent clumsy behaviour. She observes that he has an increased tendency to trip over while running. On examination, his calves were relatively slim, and the soles of his feet were arched. Ankle dorsiflexors were noted to be weak, and the deep tendon reflexes were absent. What is the most probable diagnosis?
Your Answer: Charcot–Marie–Tooth syndrome
Explanation:The patient’s clinical presentation is highly suggestive of Charcot–Marie–Tooth syndrome.It is a hereditary sensory and motor neuropathy. It is also the commonest cause of inherited peripheral neuropathy. The lower motor neuron signs are usually mild in childhood, the age of onset is very variable, and the distal weakness can take years to progress. It is not fatal and does not affect the normal life expectancy.
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This question is part of the following fields:
- Neurology And Neurodisability
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Question 11
Correct
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A 1-month-old boy was brought to the ED by his mother because he has been irritable and feeding poorly for the last 24 hours. His CXR shows cardiomegaly but with clear lung fields while his ECG shows a regular narrow complex tachycardia with difficulty identifying the P wave. The boy is conscious but has cold extremities. What is the most appropriate next step?
Your Answer: Synchronized DC cardio-version
Explanation:The most possible diagnosis is SVT. The boy is suffering from hemodynamic instability, as indicated by his cold extremities. DC cardioversion is the treatment of choice.
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This question is part of the following fields:
- Cardiovascular
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Question 12
Correct
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A 15-year-old male presents with a depressed skull fracture, which was surgically managed. Over the next few days, he complains of double vision on walking downstairs and reading. On testing ocular convergence, the left eye faces downward and medially, but the right side does not.Which of the following injured nerves is most likely responsible for the patient's symptoms?
Your Answer: Trochlear
Explanation:Based on the clinical scenario provided, the most probable nerve injured in this patient would be the trochlear nerve. The trochlear nerve has a relatively long intracranial course, and this makes it vulnerable to injury in head trauma. Head trauma is the most frequent cause of acute fourth nerve palsy. A 4th nerve palsy is the most common cause of vertical diplopia. The diplopia is at its worst when the eye looks medially which it usually does as part of the accommodation reflex when walking downstairs.
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This question is part of the following fields:
- Ophthalmology
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Question 13
Correct
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Which of the given clinical findings is the hallmark of Trisomy 21?
Your Answer: Hypotonia
Explanation:Trisomy 21 (Down’s syndrome)is a genetic disorder characterized by the presence of an extra copy of chromosome 21 in all the body cells, mostly due to non-disjunction during gametogenesis. Robertsonian translocation occurs only in about 2-4% of the cases. A variety of clinical features are found in trisomy 21 due to multi-system involvement but the hallmark is hypotonia, which is present in almost all the cases of trisomy 21. Different types of leukemias are also found in association with down’s syndrome, but they are not the hallmark. Atlantoaxial subluxation is secondary to hypotonia, which induces joint and ligament laxity. Other clinical findings are hypothyroidism, Alzheimer’s disease, Hirschsprung’s disease, and pulmonary hypertension.
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This question is part of the following fields:
- Genetics And Dysmorphology
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Question 14
Incorrect
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Which of the following is not associated with hirsutism?
Your Answer: Cushing's syndrome
Correct Answer: Delayed puberty
Explanation:Hirsutism is the growth of excess hair in androgen dependent areas or in a male pattern. The phenomenon is found in conditions where there is abnormal androgen action. This can occur in adrenal lesions including congenital adrenal hyperplasia, and Cushing syndrome, or a failure to produce adequate female hormones such as PCOS and premature menopause. Similarly, drugs such as anabolic steroids, danazol and minoxidil can also cause hirsutism. Delayed puberty is unlikely to cause hirsutism.
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This question is part of the following fields:
- Dermatology
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Question 15
Correct
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A 7-week-old infant is brought to the emergency department by his mother. She complains that the child is having episodes of non-bilious vomiting for the past 10 days. She observed that the episodes typically occur directly after feeding and notes that the volume brought up varies, but that her baby does seem to be very hungry and has not gained much weight. What is the most probable diagnosis for this infant?
Your Answer: Pyloric stenosis
Explanation:The most probable diagnosis for this patient would be congenital hypertrophic pyloric stenosis.Congenital Hypertrophic Pyloric Stenosis (CHPS):Pyloric stenosis should be ruled out in any baby who presents with a long-term history of vomiting and failure to thrive. Infants typically present with projectile, non-bilious vomiting and are said to be hungry and wanting to feed despite poor weight gain. A blood gas would be helpful in this instance, although the diagnosis can be made more accurately by observing the stenosis during ultrasound. Many infants have symptoms of gastroesophageal reflux disease, although only a small minority are unable to gain weight adequately. A UTI in infants can present with non-specific symptoms, but they might have a fever and can show poor feeding. Malrotation will present with bilious vomiting.The definitive surgical management is the Ramsteadt’s pyloromyotomy.
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This question is part of the following fields:
- Gastroenterology And Hepatology
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Question 16
Correct
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A 17-year-old boy is brought to the emergency after being stabbed in the upper arm and the median nerve is transected. Impaired function can be demonstrated in which of the following muscle/s?
Your Answer: Abductor pollicis brevis
Explanation:The median nerve is a peripheral nerve originating in the cervical roots C5–T1 of the brachial plexus. It supplies motor innervation to the anterior forearm flexors, the thenar muscles, and the two lateral lumbricals as well as sensory innervation to the lateral palm and anterior, lateral three and a half fingers. Motor and sensory deficits depend on whether the lesion is proximal (above the elbow) or distal (below the elbow). While proximal lesions present with the “hand of benediction,” distal lesions present with either the “pinch sign” (anterior interosseous nerve syndrome) or, in the case of carpal tunnel syndrome, with mildly impaired thumb and index finger motion. Both proximal lesions and carpal tunnel syndrome result in reduced sensation in the area of the thumb, index and middle finger. Anterior interosseus nerve syndrome does not cause any sensory deficits. Chronic injuries to the nerve result in atrophy of median nerve innervated muscles while acute injuries do not have this feature. Treatment is mostly conservative and focuses on rest and immobilization.
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This question is part of the following fields:
- Musculoskeletal
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Question 17
Correct
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For a given condition, disease or attribute, there will be a proportion of people in a population who have it at a specified point in time or over a specified period of time. Which of following is the best term which describes the above?
Your Answer: Prevalence
Explanation:Prevalence:
This is the proportion of individuals in a population who have a specific condition, disease, or attribute at a given point in time or over a specific period.
Incidence:
This is the number of new cases of a specific condition, disease, or attribute that develop in a population during a specified period of time.
Specificity:
This refers to the ability of a test to correctly identify those without the condition (true negative rate).
Sensitivity:
This refers to the ability of a test to correctly identify those with the condition (true positive rate).
Probability:
This is a measure of the likelihood that an event will occur. In the context of diseases, it can refer to the likelihood of developing a condition.
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This question is part of the following fields:
- Epidemiology And Statistics
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Question 18
Correct
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Which of the following is a risk factor for intrauterine growth restriction?
Your Answer: Foetal echogenic bowel
Explanation:Intrauterine growth restriction refers to the failure of the fetus to grow in accordance with the weeks of gestation. There are two types of growth restriction, symmetrical and asymmetrical. Causes include various genetic abnormalities, fetal infections, maternal health conditions, etc. Risk factors for the development of IUGR include fetal echogenic bowel, maternal age above 40 years, low PAPP-A levels, maternal smoking or cocaine use, etc. Fetal echogenic bowel implies a brighter than usual fetal intestines on ultrasonography. It is a marker associated with trisomy 21, which is a cause of IUGR.
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This question is part of the following fields:
- Neonatology
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Question 19
Correct
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A 10-year-old boy was sent for an x-ray of the leg because he was complaining of pain and swelling. The x-ray showed the classic sign of Codman's triangle. What is the most likely diagnosis of this patient?
Your Answer: Osteosarcoma
Explanation:Codman’s triangle is the triangular area of new subperiosteal bone that is created when a lesion, often a tumour, raises the periosteum away from the bone. The main causes for this sign are osteosarcoma, Ewing’s sarcoma, eumycetoma, and a subperiosteal abscess.
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This question is part of the following fields:
- Musculoskeletal
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Question 20
Correct
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An 8-year-old girl returns from holiday in Greece, complaining of ear discharge and tragal tenderness. The exam shows a normal tympanic membrane and ear cleaning was done. What is the next step in management?
Your Answer: Antibiotic drop with steroid
Explanation:The symptoms and signs described are suggestive of otitis externa. The key treatment for otitis externa is ear cleaning and antibiotic drops with steroid.
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This question is part of the following fields:
- ENT
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Question 21
Incorrect
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A family of five members presents to the genetics clinic for further evaluation. The father, one boy and one girl present with a short stature, large heads, short digits, and trident hands. Genetic evaluation reveals they are all heterozygotes for a specific mutation. The rest of the family, the mother and the other daughter, do not carry this mutation. What is the pattern of inheritance?
Your Answer: Autosomal dominant with variable penetrance
Correct Answer: Autosomal dominant with complete penetrance
Explanation:In this case, the affected individuals are all heterozygotes. Therefore, the mutation is autosomal dominant. Also, the mother does not carry the mutation, further confirming the autosomal dominant nature of the disease, which is most probably achondroplasia.
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This question is part of the following fields:
- Genetics And Dysmorphology
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Question 22
Correct
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A 14-year-old female was found to have a 1/6 systolic ejection murmur on regular check-up and was subsequently referred to a cardiologist. A thorough physical examination reveals long upper extremities with thin slender fingers, with a high arched palate and excessive ligamentous laxity. Her thumb can be bent back easily to touch her radius. ECG reveals sinus bradycardia that is consistent with aerobic conditioning. She also had an echo done. In reference to her most likely diagnosis, which of the following is the most serious cardiac complication associated to this condition?
Your Answer: Aortic dissection
Explanation: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.
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This question is part of the following fields:
- Genetics And Dysmorphology
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Question 23
Incorrect
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Which of the following features is true of Alport syndrome?
Your Answer: Autosomal recessive is the most common mode of inheritance
Correct Answer: It is caused by defects in collagen
Explanation:Alport syndrome is a genetic condition characterized by kidney disease, hearing loss, and eye abnormalities. Alport syndrome can have different inheritance patterns. About 80 percent of cases are caused by mutations in type IV collagen genes (COL4A5) and are inherited in an X-linked autosomal recessive pattern, although other inheritance patterns exist. Alport syndrome has autosomal dominant inheritance in about 5 percent of cases.
People with Alport syndrome experience progressive loss of kidney function. Almost all affected individuals have blood in their urine (haematuria), which indicates abnormal functioning of the kidneys. Many people with Alport syndrome also develop high levels of protein in their urine (proteinuria). The kidneys become less able to function as this condition progresses, resulting in end-stage renal disease (ESRD).
People with Alport syndrome frequently develop sensorineural hearing loss, which is caused by abnormalities of the inner ear, during late childhood or early adolescence. Affected individuals may also have misshapen lenses in the eyes (anterior lenticonus) and abnormal coloration of the light-sensitive tissue at the back of the eye (retina). These eye abnormalities seldom lead to vision loss.
Significant hearing loss, eye abnormalities, and progressive kidney disease are more common in males with Alport syndrome than in affected females.
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This question is part of the following fields:
- Nephro-urology
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Question 24
Incorrect
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Which of the following conditions is inherited in an autosomal recessive fashion?
Your Answer: Hereditary spherocytosis
Correct Answer: Cystinosis
Explanation:Cystinosis is a condition characterized by accumulation of the amino acid cystine (a building block of proteins) within cells. This condition is inherited in an autosomal recessive pattern.Excess cystine damages cells and often forms crystals that can build up and cause problems in many organs and tissues. The kidneys and eyes are especially vulnerable to damage| the muscles, thyroid, pancreas, and testes may also be affected.There are three distinct types of cystinosis. In order of decreasing severity, they are nephropathic cystinosis, intermediate cystinosis, and non-nephropathic or ocular cystinosis.Nephropathic cystinosis begins in infancy, causing poor growth and a particular type of kidney damage (renal Fanconi syndrome) in which certain molecules that should be reabsorbed into the bloodstream are instead eliminated in the urine. The kidney problems lead to the loss of important minerals, salts, fluids, and many other nutrients. The loss of nutrients impairs growth and may result in soft, bowed bones (hypophosphatemic rickets), especially in the legs. The nutrient imbalances in the body lead to increased urination, thirst, dehydration, and abnormally acidic blood (acidosis). By about the age of 2, cystine crystals may be present in the clear covering of the eye (cornea). The build-up of these crystals in the eye causes pain and an increased sensitivity to light (photophobia). Untreated children will experience complete kidney failure by about the age of 10. Other signs and symptoms that may occur in untreated people, especially after adolescence, include muscle deterioration, blindness, inability to swallow, diabetes, thyroid and nervous system problems, and an inability to father children (infertility) in affected men.The signs and symptoms of intermediate cystinosis are the same as nephropathic cystinosis, but they occur at a later age.
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This question is part of the following fields:
- Genetics And Dysmorphology
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Question 25
Correct
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Two boys were playing when one of them brought the forearm of the other behind his back. This resulted in a stretching of the lateral rotator of the arm. Which of the following muscles was most likely to have been involved?
Your Answer: Infraspinatus
Explanation:There are two lateral rotators of the arm, the infraspinatus and the teres minor muscles. The infraspinatus muscle receives nerve supply from C5 and C6 via the suprascapular nerve, whilst the teres minor is supplied by C5 via the axillary nerve.
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This question is part of the following fields:
- Musculoskeletal
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Question 26
Correct
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Which of following statements with regards to the developmental problems found in Fragile X syndrome is the most accurate?
Your Answer: Around one third of children with FXS meet diagnostic criteria for autistic spectrum disorder
Explanation:Fragile X syndrome is a genetic syndrome associated with neuro-developmental problems such as learning disabilities and cognitive impairment, with many affected children having mild to moderate intellectual disability. About a third of children have features of autism spectrum disorder and ADHD which affects their communication skills and social interactions. As such, affected individuals usually have delayed speech development and poor nonverbal skills such as gaze aversion. Symptoms tend to worsen with age into adolescence as the demands on their intellect becomes greater. Pre-mutation carriers, who posses smaller genetic repeat expansions, have been found to be associated with some neurodevelopment and other medical problems.
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This question is part of the following fields:
- Neurology And Neurodisability
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Question 27
Incorrect
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A 11 year girl presents to the A&E department with a full thickness burn to her right arm, which she got when a firework that she was playing with exploded. Which statement is not characteristic of the situation?
Your Answer: Absence of, or few, blisters
Correct Answer: The burn area is extremely painful until skin grafted
Explanation:Answer: The burn area is extremely painful until skin graftedThird-degree burns destroy the epidermis and dermis. Third-degree burns may also damage the underlying bones, muscles, and tendons. The burn site appears white or charred. There is no sensation in the area since the nerve endings are destroyed. These are not normally painful until after skin grafting is done since the nerve endings have been destroyed.
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This question is part of the following fields:
- Emergency Medicine
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Question 28
Correct
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A 5-month-old baby was brought by the mother for assessment. The baby can sit with support but not on his own. On examination, there is palmar grasp. How is the current development of this child?
Your Answer: Normal
Explanation:All the given development milestones are compatible with the given age.
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This question is part of the following fields:
- Child Development
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Question 29
Correct
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A new-born baby is born with a midline lumbosacral cystic lesion. Occipitofrontal circumference was above the 90th percentile.The next best step is?
Your Answer: Cranial ultrasound
Explanation:The baby may have hydrocephalus and no surgery can be done until it is excluded.Cranial sonography is an important part of neonatal care in general, and high-risk and unstable premature infants, in particular. It allows rapid evaluation of infants in the intensive care units without the need for sedation and with virtually no risk. Expectedly, sonography represents an ideal imaging modality in neonates due to its portability, lower cost, speed, and lack of ionizing radiations. Although there are numerous indications for cranial sonography, it appears to be most useful for detection and follow-up of intracranial haemorrhage, hydrocephalus, and periventricular leukomalacia (PVL).
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This question is part of the following fields:
- Neonatology
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Question 30
Correct
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A 7-month-old abandoned baby with congenital non-communicating hydrocephalus is hosted by a clinic at its new-born hostel. A CT scan of the baby's brain reveals what might be a blockage of the ventricular system between the third and the fourth ventricles. Which of the following is the most likely blocked structure?
Your Answer: Cerebral aqueduct
Explanation:The drainage of cerebral spinal fluid from the third ventricle to the fourth ventricle is carried out by the cerebral aqueduct. The cerebral aqueduct is the narrowest passageway in the entire ventricular system and thus forms the most common site of blockage of flow of cerebrospinal fluid. The interventricular foramen allows passage of CSF to the third ventricle. The foramen of Luschka and Magendie are located on the fourth ventricle and allow passage of CSF to the subarachnoid space from the ventricular system. The pontine cistern is a space located on the ventral aspect of the pons. The cisterna magna is an opening on the subarachnoid space between the pia matter and the arachnoid.
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This question is part of the following fields:
- Neurology
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