Embryologically the testes are retroperitoneal structures in the posterior abdominal wall, attached to the anterolateral abdominal wall by the gubernaculum. The gubernaculum ‘pulls’ the testes through the deep inguinal ring, inguinal canal and superficial inguinal ring and over the pelvic brim. The gubernaculum is preceded by the processus vaginalis that is derived from the peritoneum anterior to the testes. The processus vaginalis pushes the muscle and fascial layers. These eventually make up the canal and the spermatic cord, into the scrotum. The gubernaculum persists as the scrotal ligament while part of the processus vaginalis remains as a bursa-like sac i.e. the tunica vaginalis testes. The testes therefore could be caught in any one of these places along its path of descending. The testes are never in the perineum.

The most probable diagnosis for this patient would be Coarctation of Aorta (CoA).Infants with CoA present within the first few weeks of life with signs suggestive of congestive cardiac failure and general circulatory shock. In these patients, the aorta is supplied by the right ventricle, via the ductus arteriosus. Pathophysiology:When the left ventricle supplies the aorta via the aortic isthmus, children are usually asymptomatic or may present with occasional complaints of leg pain. Associated cardiac anomalies are uncommon but for a bicuspid aortic valve, which is present in approximately 50% of cases. Good collateral circulation usually develops in these patients, which in the long term, causes notching of ribs. Clinical Presentation:Clinically, there may be hypertension in the upper limbs (or higher BP readings than in the lower limbs), and leg pulses are absent, or weak and delayed. A systolic click and aortic ejection systolic murmur are heard, caused by the bicuspid aortic valve. Management:The primary medical management is to treat hypertension. After stabilization, the patient can undergo definitive surgical repair. Transcatheter balloon angioplasty of the coarctation is controversial, but ballooning +/- stenting of re-coarctation following surgery is commonly performed.Systemic hypertension may occur following repair, even in the absence of re-coarctation necessitating the re-initiation/continuation of antihypertensive therapy in these patients.

This is the clinical picture of dermatitis herpetiformis associated with gluten-sensitive enteropathy. To establish the diagnosis, you should measure the coeliac antibodies. Darrier’s sign (where the skin urticates when it is stroked) is positive in urticaria pigmentosa.

The main result of a correlation is called the correlation coefficient (or r). It ranges from -1.0 to +1.0. The closer r is to +1 or -1, the more closely the two variables are related.If r is close to 0, it means there is no relationship between the variables. If r is positive, it means that as one variable gets larger the other gets larger. If r is negative it means that as one gets larger, the other gets smaller (often called an inverse correlation).

The skin lesion described is the typical presentation of a keloid scar.Keloid scars extend beyond the limits of the incision.Note:Surgical wounds are either incisional or excisional and either clean, clean-contaminated or dirty. The main stages of wound healing include:- Haemostasis:It occurs minutes to hours following injury. It is characterised by the vasospasm in adjacent vessels, platelet plug formation and generation of fibrin rich clot.- Inflammation: It occurs typically 1-5 days after the injury. Neutrophils migrate into the wound (this is often impaired in diabetes). Growth factors, including basic fibroblast growth factor and vascular endothelial growth factor, are released in this phase. Fibroblasts replicate within the adjacent matrix and migrate into wound, while macrophages and fibroblasts couple matrix regeneration and clot substitution.- Regeneration: It occurs typically between 7-56 days after the injury. The factors that stimulate this phase are platelet-derived growth factor and transforming growth factor. They stimulate fibroblasts and epithelial cells. Fibroblasts produce a collagen network. Furthermore, they cause angiogenesis and thus wound healing.- Remodelling: This is considered the longest phase of the healing process and may last up to one year (or longer). During this phase, fibroblasts become differentiated (myofibroblasts), and these facilitate wound contraction. Collagen fibres are remodelled, and microvessels regress, leaving a pale scar.Clinical correlation:Abnormal scar formation:- Hypertrophic scars:It is the condition where excessive amounts of collagen are produced within a scar. Nodules may be present histologically containing randomly arranged fibrils within and parallel fibres on the surface. The tissue itself is confined to the extent of the wound itself and is usually the result of a full-thickness dermal injury. They may go on to develop contractures.- Keloid scars: This is also a condition where excessive amounts of collagen occur within a scar. A keloid scar will typically pass beyond the boundaries of the original injury. They do not contain nodules and may occur following even trivial injury. They do not regress over time and may recur following removal.

Hyperkalaemia presents with high voltage (peaked) T waves on ECG. Other features on ECG include smaller p-waves and wider QRS complexes.

This patient has Wilson’s disease. They Kayser-Fleischer ring (ring that encircles the iris) is diagnostic of this. Low serum copper is seen in Wilson’s disease. With the Kayser-Fleischer ring, this makes all of the other answer choices incorrect.

Answer: Acute Epstein Barr virus infectionThe Epstein–Barr virus is one of eight known human herpesvirus types in the herpes family, and is one of the most common viruses in humans. Infection with Epstein-Barr virus (EBV) is common and usually occurs in childhood or early adulthood.EBV is the cause of infectious mononucleosis, an illness associated with symptoms and signs like:fever,fatigue,swollen tonsils,headache, andsweats,sore throat,swollen lymph nodes in the neck, andsometimes an enlarged spleen.Although EBV can cause mononucleosis, not everyone infected with the virus will get mononucleosis. White blood cells called B cells are the primary targets of EBV infection.Petechiae on the palate are characteristic of streptococcal pharyngitis but also can be seen in Epstein–Barr virus infection, Arcanobacterium haemolyticum pharyngitis, rubella, roseola, viral haemorrhagic fevers, thrombocytopenia, and palatal trauma.

Polycythaemia is described as an abnormal increase in the red cell mass. As this influences hyper-viscosity, a peripheral venous sample of blood haematocrit can be used to determine the packed cell volume. Polycythaemia is present if the venous haematocrit is >65% or <22g/dl if converted into a haemoglobin value. Though it is the method of choice for screening, capillary blood samples obtained though heel pricks in new-born may be as much as 15% higher than venous samples and thus high values must be confirmed with a venous sample.

Diazepam given rectally may be helpful in treating prolonged convulsions outside and within hospital when intravenous injection is not possible. A rectal dose of 0.5 mg/kg (maximum 10 mg) of injectable diazepam, undiluted or diluted with a 50% propylene glycol solution, can stop seizures in up to 80% of children. There are few adverse reactions. Seizures in children usually cease spontaneously within 5-10 minutes and are rarely associated with significant sequelae. The chance of a seizure stopping spontaneously decreases significantly after 10-15 minutes. Similarly, the efficacy of anticonvulsant medication decreases after 10-15 minutes of fitting and the risk of adverse effects increases. Convulsive seizures lasting longer than 30 minutes constitute status epilepticus and may be complicated by cardio respiratory depression and brain injury. Diazepam or clonazepam, given intravenously, is generally the drug of choice for the emergency treatment of convulsive status epilepticus. Intravenous diazepam may be difficult to administer to the young convulsing child and, because of the need for intravenous access, is not ideal for rapid treatment in the community by non-medical carers.

Renal scaring resulting from urinary tract infections can best be determined using Dimercaptosuccinic acid (DMSA) scintigraphy. The scan utilises technetium-99 mixed with the DMSA which is injected into the bloodstream. The radiological dye is taken up by the kidney where it binds to the proximal convoluted tubules. It therefore detects the size, shape and position of the kidney and any scars but is not as useful in assessing dynamic renal excretion. Ultrasound scans are better suited to assess hydronephrosis and dilated ureters. MAG3 scans and MCUG are able to determine the function of kidneys and detect obstructions such as posterior urethral valves and reflux.

3,4-methylenedioxy-methamphetamine (MDMA) is a synthetic drug that alters mood and perception (awareness of surrounding objects and conditions). It is chemically similar to both stimulants and hallucinogens, producing feelings of increased energy, pleasure, emotional warmth, and distorted sensory and time perception. MDMA’s effects last about 3 to 6 hours, although many users take a second dose as the effects of the first dose begin to fade. Over the course of the week following moderate use of the drug, a person may experience:irritabilityimpulsiveness and aggressiondepressionsleep problemsanxietymemory and attention problemsdecreased appetitedecreased interest in and pleasure from sex

The diagnosis of scabies can often be made clinically in patients with a pruritic rash and characteristic linear burrows. Definitive testing relies on the identification of mites or their eggs, eggshell fragments, or scybala. This is best undertaken by placing a drop of mineral oil directly over the burrow on the skin and then superficially scraping longitudinally and laterally across the skin with a scalpel blade. (Avoid causing bleeding.) Scraping 15 or more burrows often produces only 1 or 2 eggs or mites, except in a case of crusted scabies, in which many mites will be present. The sample is placed on a microscope slide and examined under low and high power. Potassium hydroxide should not be used, since it can dissolve mite pellets. Failure to find mites is common and does not rule out the diagnosis of scabies.

This patient in question is most likely suffering from inflammatory bowel disease, probably ulcerative colitis. The most valuable investigation that can assess the severity and extent of the disease, including the opportunity to obtain biopsies is a colonoscopy.Other options:Barium studies and abdominal x-rays do not give sufficient information. While they can provide indicative evidence, only a colonoscopy-guided biopsy can confirm IBD.Radio-isotope scans will help in identifying a focus such as a Meckel’s diverticulum, and angiography is rarely indicated unless a vascular lesion is suspected of causing the intestinal bleed.

Adrenaline (epinephrine) narrows blood vessels and opens airways in the lungs. These effects can reverse severe low blood pressure, wheezing, severe skin itching, hives, and other symptoms of an allergic reaction.

Progressive vomiting due to pyloric stenosis leads to hypochloraemic, hypokalaemic, metabolic alkalosis.

The Chi squared test is used to find the relationship between two variables, determining whether they are not independent of each other. This test of statistical significance allows you to determine the degree of confidence with which you can accept or reject the null hypothesis. The student t test compares the significant differences in data means, while rank correlation, linear regression and the correlation coefficient all help to measure the linear relationship between variables.

In the pattern of mendelian inheritance, X- linked dominant inheritance means that all who inherit the X chromosome will present with the condition. In the case of maternal x-linked inheritance sons and daughters have an equal chance of inheriting the condition as there is a 50% chance of inheriting the defective X chromosome from their mother as opposed to a non affected X chromosome from their father. However in paternal X-linked dominant inheritance, sons will be unaffected as they inherit a Y chromosome from their father while daughters are sure to inherit the defective X-chromosome.

Anorectal malformations (ARMS) are also known as imperforate anus (IA). This is an umbrella term for a group of birth defects which affect the anorectal area.During a normal bowel movement, solid waste passes from the colon (large intestine) to the rectum (the final section the colon) and through the anus. When a child has an ARM, the rectum and the anus do not develop properly.Some types of ARM can cause constipation, faecal and / or urinary incontinence, infections and other problems. Some of these problems are very minor and easy to treat, with great long-term prognosis. Others are complex and affect multiple areas of life, such as sexual function and urinary and bowel control.

The perinatal mortality rate is defined as the number of perinatal deaths per 1000 total births. Perinatal death includes the death of a live-born neonate within 7-days of life (early neonatal death) and the death of a fetus ≥ 22 weeks of gestation (stillbirth). Hence, the perinatal mortality rate is calculated by dividing the number of still births+ the number of early neonatal deaths by 1000 births.

Although initially thought to affect only boys, girls with DMD also have an estimated 10% chance of inheriting the condition. In girls, DMD may present with all or some clinical manifestations.

The differentials of the child’s condition are likely to include an Iron deficiency anaemia, or a hemoglobinopathy such as sickle cell disease or thalassemia based on the presentation of pallor, growth failure and easy fatiguability. While the full blood count and film present a hypochromic microcytic anaemia with reticulocytosis, the normal serum ferritin levels rule out iron deficiency anaemia. Thalassemia is to be suspected over sickle cell disease as the patient comes from the Mediterranean region known for a high incidence of thalassemia. Sickle cell anaemia also tends to present with normocytic normochromic red blood cells, with many sickled cells. Vitamin B12 deficiency and Aplastic anaemia are ruled out as they present with a macrocytic anaemia, and a decrease in white blood cells, platelets and red blood cells respectively.

Nonspecific triggers of inflammation in patients with atopic dermatitis may include physical or chemical irritants. The following simple measures should be followed in daily life to reduce the frequency and severity of irritant-induced atopic dermatitis flares :Skin care products that contain alcohol and astringents should be avoided.New clothes should be laundered before use to remove formaldehyde and other chemicals.Liquid detergents are preferred over powder detergents for laundering clothes, as liquids are easier to rinse out. A second rinse cycle may also improve removal of residual detergent.Patients should shower immediately after swimming in chlorinated pools and should subsequently apply moisturizer.Fragrance-free skin products that are hypoallergenic or made for sensitive skin may be less irritating than other kinds of skin products.Prenatal and postnatal probiotic supplementation may be helpful in preventing the development of atopic dermatitis in young children. In a 2008 meta-analysis, the most commonly studied probiotic was Lactobacillus rhamnoses GG. Larger, randomized controlled studies are needed to confirm these initial findings.Breastfeeding during the first 4 months of life may reduce the incidence and severity of childhood atopic disease but only modestly and only in those at high risk.

Arnold-Chiari malformation type II is one of the congenital hindbrain abnormalities that leads to a disruption of the relationship between different hindbrain structures. It is characterized by congenital hydrocephalus, herniation of cerebellar tonsils into the pinal canal with an enlarged 4th ventricle, spina bifida associated with myelomeningocele, and various levels of denervation atrophy of the muscles of the lower limb. The association of type II Arnold-Chiari with myelomeningocele carries importance from an etiological perspective, forming the basis of CSF escape theory.

A ventricular septal defect (VSD) is a common form of congenital heart defects and is characterised by the presence of a hole in the wall that separates the right from the left ventricle. Medium or large defects can cause many complications. One of these complication is Eisenmenger syndrome, characterised by reversal of the shunt (from left-to-right shunt into a right-to-left) ,cyanosis and pulmonary hypertension.

Adrenal insufficiency is a serious medical condition that leads to inadequate secretion of corticosteroids. There are three main types of adrenal insufficiency: primary, secondary, and tertiary, based on the location of the abnormality. Primary adrenal insufficiency is caused by any pathology located inside the adrenal glands. The most common cause of primary adrenal insufficiency is Addison’s disease, which is an autoimmune condition. Adrenoleukodystrophy is an X-linked neurodegenerative disease that also causes primary adrenal insufficiency. Secondary adrenal insufficiency is caused by any pathological impairment of the pituitary gland or the hypothalamus. The important causes of secondary adrenal insufficiency include iatrogenic (steroid use), pituitary tumours like craniopharyngioma, and conditions leading to panhypopituitarism like Sheehan’s syndrome. Tertiary adrenal insufficiency is caused by the deficiency of the corticotropin-releasing hormone. Hypoparathyroidism does not cause adrenal insufficiency.

CSF is produced mainly by a structure called the choroid plexus in the lateral, third and fourth ventricles. CSF flows from the lateral ventricle to the third ventricle through the interventricular foramen (also called the foramen of Monro). The third ventricle and fourth ventricle are connected to each other by the cerebral aqueduct (also called the Aqueduct of Sylvius). CSF then flows into the subarachnoid space through the foramina of Luschka (there are two of these) and the foramen of Magendie (only one of these).Absorption of the CSF into the blood stream takes place in the superior sagittal sinus through structures called arachnoid villi . When the CSF pressure is greater than the venous pressure, CSF will flow into the blood stream.

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

Erythema nodosum (EN) is an acute, nodular, erythematous eruption that usually is limited to the extensor aspects of the lower legs. It is a delayed hypersensitivity reaction to a variety of antigens| circulating immune complexes have not been found in idiopathic or uncomplicated cases but may be demonstrated in patients with inflammatory bowel disease.Currently, the most common cause of erythema nodosum is a streptococcal infection in children and streptococcal infection and sarcoidosis in adultsIn most patients, erythema nodosum is a self-limited disease and requires only symptomatic relief using nonsteroidal anti-inflammatory drugs (NSAIDs), cool wet compresses, elevation, and bed rest.

Neurofibromatosis Type 1 (also known as von Recklinghausen disease) does not present with cataracts.The eye findings in NF1 are Lisch’s nodules, which are pigmentary lesions seen on the iris and constitute one of the major diagnostic features in this condition. Note:Interestingly, in another syndrome closely related to it, Neurofibromatosis type 2 (NF-2), cataracts can occur. Early detection in family members may be made by finding lens opacities (both congenital polar cataracts and posterior lenticular opacities). Other options:- Incontinentia pigmenti is an X-linked dominant disorder with pigmentary skin changes, mental retardation and eye involvement in 40% of cases. – Myotonic dystrophy is a triplet-repeat disorder with neurological symptoms and cataracts. – Lowe syndrome (oculo-cerebro-renal syndrome) is an X-linked recessive condition. Males with this X-linked recessive condition have cataracts, hypotonia, mental retardation, generalised aminoaciduria and renal tubular acidosis with hypophosphatemia. – Wilson disease is an inborn error of copper metabolism. The clinical features include hepatic involvement, progressive neurological features, eye involvement, including Kayser–Fleischer rings and cataracts.