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.

Breath-holding spells are usually caused by either a change in the child’s breathing or a slowing of the heart rate. In some children, breath-holding spells may be related to iron deficiency anaemia, a condition in which the body doesn’t produce a normal number of red blood cells. Conclusion: Not only Iron deficiency anaemia but also iron deficiency alone without anaemia is associated with a risk of high-frequency cyanotic breath holding spells. Iron therapy results in reduction in spells’ frequency which was correlated with increasing ferritin and iron levels.

One of the most common congenital viral infections is cytomegalovirus infection. It is caused by herpesvirus type 5. The clinical features include failure to thrive, intellectual disability, epilepsy, and microcephaly. The most common clinical complication is sensorineural deafness. The drug of choice for the treatment of neonatal CMV infection is ganciclovir, an anti-viral drug that has shown to prevent deafness.

To quantify differences between percentages you can use Fisher’s exact test.Odds ratios, relative risks and number needed to treat are ways of quantifying differences between percentages in two groups, however are not in themselves significance tests.

Synchronized IMV (SIMV) with pressure support, used in the alert infant. SIMV guarantees a minimum minute volume while allowing the patient to trigger spontaneousbreaths at a rate and volume determined by the patient. Extra breaths are boosted with pressure support. Tidal Volume (Vt) is normally approximately 6-10 mL/kg and 4-6 ml/kg in the preterm.Respiratory rate (RR) is usually 30-60 BPM. Tidal volume and respiratory rate are relatedto respiratory minute volume as follows: Vm(mL/min) = Vt x RR .This baby is overventilated with a low CO2. Tidal volumes should generally be targeted at 4-6 ml/kg and this baby is being targeted at 9 ml/kg which exposes the baby to damage to the distal airways from this ventilation which can lead to bronchopulmonary dysplasia.

According to WHO, the treatment protocol in severely dehydrated children, is to infuse a bolus of isotonic crystalloid over 20-30 min at 30ml/kg to children less than 12 months of age followed by giving the remaining fluid over 5 hours for infants. Reference: World Health Organisation, the treatment of diarrhoea, a manual for physical and senior health workers.

A 10 year old child, with a history of URTI and haematuria, presents a picture consistent with a diagnosis of IgA nephropathy. This condition can present with proteinuria and generalized swelling. However, an important differentiating point from rapidly progressive GN is the duration. IgA nephropathy is usually <10 days (commonly 4-5 day history of infection).

The level of statistical significance is often expressed as a p-value between 0 and 1. The smaller the p-value, the stronger the evidence that you should reject the null hypothesis.A p-value less than 0.05 (typically ≤ 0.05) is statistically significant. It indicates strong evidence against the null hypothesis, as there is less than a 5% probability the null is correct (and the results are random). Therefore, we reject the null hypothesis, and accept the alternative hypothesis.However, this does not mean that there is a 95% probability that the research hypothesis is true. The p-value is conditional upon the null hypothesis being true is unrelated to the truth or falsity of the research hypothesis.A lower p-value is sometimes interpreted as meaning there is a stronger relationship between two variables. However, statistical significance means that it is unlikely that the null hypothesis is true (less than 5%).To understand the strength of the difference between two groups (control vs. experimental) a researcher needs to calculate the effect size.

Precocious Puberty is the development of secondary sexual characteristics before the age of 8 in females, and 9 in males. The first sign of early puberty in males is testicular enlargement, followed by growth of the penis and the scrotum at least a year after. Precocious puberty in boys in uncommon and usually has an organic cause leading to excess secretion of testosterone. These can be gonadotrophin dependent in the case of an inter cranial lesion, where the testes would be bilaterally enlarged, or from excess production from the adrenal gland in the case of adrenal hyperplasia or a tumour.

The baby most probably has dystrophic epidermolysis bullosa, a primarily autosomal dominant disorder associated with keratin 5 and 14 defects. Initial management consists of supportive measures such as protecting the skin.

The symptoms of a partial generalized seizure are consistent with this patient.

The trisomy 18 syndrome, also known as Edwards syndrome, is a common chromosomal disorder due to the presence of an extra chromosome 18, either full, mosaic trisomy, or partial trisomy 18q. The condition is the second most common autosomal trisomy syndrome after trisomy 21.Currently, most cases of trisomy 18 are prenatally diagnosed, based on screening by maternal age, maternal serum marker screening, or detection of sonographic abnormalities (e.g., increased nuchal translucency thickness, growth retardation, choroid plexus cyst, overlapping of fingers, and congenital heart defects ).The main clinical features represent the clues for the diagnosis in the perinatal period and include prenatal growth deficiency, characteristic craniofacial features (dolichocephaly, short palpebral fissures, micrognathia external anomalies of the ears, and redundant skin at the back of the neck), distinctive hand posture (overriding fingers: index finger overlapping the third and 5th finger overlapping the 4th), nail hypoplasia, short hallux, underdeveloped thumbs, short sternum, and club feet and major malformations (particularly involving the heart).

The child requires frequent BP evaluation every 15 to 30 minutes. Normalisation of his BP should be achieved in a 48h interval. An ophthalmology assessment is indicated to check for acute injury of the blood vessels in the eye due to the elevated blood pressure.

Clinical diagnosis of neurofibromatosis type 1 requires the presence of at least 2 of 7 criteria. Many of these signs do not appear until later childhood or adolescence, and thus confirming the diagnosis often is delayed despite a suspicion of NF1. The 7 clinical criteria used to diagnose NF1 are as follows:- Six or more cafe-au-lait spots or hyperpigmented macules greater than 5 mm in diameter in prepubertal children and greater than 15 mm in postpubertal- Axillary or inguinal freckles (>2) – Two or more typical neurofibromas or one plexiform neurofibroma- Optic nerve glioma- Two or more iris hamartomas (Lisch nodules), often identified only through slit-lamp examination by an ophthalmologist- Sphenoid dysplasia or typical long-bone abnormalities such as pseudarthrosis- A first-degree relative (e.g., mother, father, sister, brother) with NF1

The ductus arteriosus is normally patent during fetal life; it is an important structure in fetal development as it contributes to the flow of blood to the rest of the fetal organs and structure. From the 6th week of fetal life onwards, the ductus is responsible for most of the right ventricular outflow, and it contributes to 60% of the total cardiac output throughout fetal life. Only about 5-10% of its outflow passes through the lungs.This patency is promoted by continual production of prostaglandin E2 (PGE2) by the ductus.In the foetus, the oxygen tension is relatively low, because the pulmonary system is non-functional. Coupled with high levels of circulating prostaglandins, this acts to keep the ductus open. The high levels of prostaglandins result from the little amount of pulmonary circulation and the high levels of production in the placenta.At birth, the placenta is removed, eliminating a major source of prostaglandin production, and the lungs expand, activating the organ in which most prostaglandins are metabolized. In addition, with the onset of normal respiration, oxygen tension in the blood markedly increases. Pulmonary vascular resistance decreases with this activity.Normally, functional closure of the ductus arteriosus occurs by about 15 hours of life in healthy infants born at term. This occurs by abrupt contraction of the muscular wall of the ductus arteriosus, which is associated with increases in the partial pressure of oxygen (PO2) coincident with the first breath. A preferential shift of blood flow occurs; the blood moves away from the ductus and directly from the right ventricle into the lungs. Until functional closure is complete and PVR is lower than SVR, some residual left-to-right flow occurs from the aorta through the ductus and into the pulmonary arteriesA balance of factors that cause relaxation and contraction determine the vascular tone of the ductus. Major factors causing relaxation are the high prostaglandin levels, hypoxemia, and nitric oxide production in the ductus. Factors resulting in contraction include decreased prostaglandin levels, increased PO2, increased endothelin-1, norepinephrine, acetylcholine, bradykinin, and decreased PGE receptors. Increased prostaglandin sensitivity, in conjunction with pulmonary immaturity leading to hypoxia, contributes to the increased frequency of patent ductus arteriosus (PDA) in premature neonates.Although functional closure usually occurs in the first few hours of life, true anatomic closure, in which the ductus loses the ability to reopen, may take several weeks. The second stage of closure related to the fibrous proliferation of the intima is complete in 2-3 weeks.

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.

Before the test, the patient was likely to have the disease being tested for. Their pre test odds were 2, making them twice as likely to have the disease. After testing positive, their pretest odds of 2 and the likelihood ratio of 3 are multiplied to produce 6 as the post test odds. The patient is now 6 times as likely to have the disease after the test. Likelihood ratios above 10 or below 0.1 are strong evidence to rule in and rule out a diagnosis. The negative likelihood ratio is not known here, but does not subtract from the interpretation of the outcomes in this patient.

Endothoracic fascia: the connective tissue (fascia) that is between the costal parietal pleura and the inner wall of the chest wall. Costomediastinal recess: the point where the costal pleura becomes mediastinal pleura. Costodiaphragmatic recess: is the lowest point of the pleural sac where the costal pleura becomes diaphragmatic pleura. Cupola: the part of the parietal pleura that extends above the first rib level into the root of the neck. Costocervical recess: this is a made-up term. Peritracheal fascia: a layer of connective tissue that invests the trachea.

Among the statements provided, boluses of insulin are given to treat diabetic ketoacidosis (DKA).The following methods are adopted for the treatment of DKA:- Fluids: Boluses of 10 ml/kg of normal saline. Stop at three boluses to avoid precipitating cerebral oedema. The remaining deficit has to be corrected over 48 hours. Strict input/output, U&E, and pH monitoring is necessary in such patients.- Insulin: Insulin infusion can be initiated at 0.05-0.1 unit/kg/hour. It is essential to monitor blood glucose closely, and the aim is to decrease by 2 mmol/hour.- Potassium: Initially, it will be high, but following insulin administration, the levels drop quickly as K+ enters cells with glucose, and thus, replacement is almost always necessary.- Acidosis: Bicarbonate is avoided unless pH is less than 7. Acidosis will get corrected with the correction of fluid and insulin deficits. The definitive treatment is directed towards correcting the underlying precipitants of DKA, e.g. sepsis, infections.

The most probable diagnosis in this patient would be pulmonary stenosis. Pulmonary Stenosis:Pulmonary valve murmurs are heard in the upper left sternal edge, associated with a thrill but no desaturation in the absence of an additional shunt. The ECG changes suggest right ventricular hypertrophy. Pulmonary stenosis is often well tolerated in childhood unless severe. These should be monitored with serial echocardiography, and balloon pulmonary valvoplasty should be considered once the pressure gradient reaches 64 mmHg.Other options:- Atrial septal defect: While atrial septal defects are associated with right ventricular outflow tract murmurs, they would not cause a thrill.- Patent ductus arteriosus: PDA murmurs can be audible in the left upper sternal edge, but would normally be audible in the left infraclavicular area and be continuous rather than ejection systolic. This left to right shunt would not cause desaturation but does cause left-sided volume loading and hence left-sided ECG changes.- Tetralogy of Fallot: Ventricular septal defect, overriding aorta, subpulmonary stenosis, and right ventricular hypertrophy. This would often cause a ULSE murmur with a thrill and RVH on ECG. However, this degree of obstruction would cause shunting from right to left, and this child would be desaturated.- Ventricular septal defect: Isolated ventricular septal defects cause pansystolic murmurs at the left lower sternal edge. They would have left-sided ECG changes and normal saturations (in the absence of pulmonary hypertension).

The Moro reflex is a normal primitive, infantile reflex. It can be seen as early as 25 weeks postconceptional age and usually is present by 30 weeks postconceptional age.6 month old milestones:Social and Emotional:Knows familiar faces and begins to know if someone is a stranger Likes to play with others, especially parents Responds to other people’s emotions and often seems happy Likes to look at self in a mirror Language/Communication:Responds to sounds by making sounds Strings vowels together when babbling (ah,ť eh,ť ohť) and likes taking turns with parent while making sounds Responds to own name Makes sounds to show joy and displeasure Begins to say consonant sounds (jabbering with m,ť bť) Cognitive (learning, thinking, problem-solving):Looks around at things nearby Brings things to mouth Shows curiosity about things and tries to get things that are out of reach Begins to pass things from one hand to the other Movement/Physical Development:Rolls over in both directions (front to back, back to front) Begins to sit without support When standing, supports weight on legs and might bounce Rocks back and forth, sometimes crawling backwards before moving forward

The most important test recommended among the given options is the measurement of creatine kinase levels.The child presents with a gross motor developmental delay, and multiple investigations can be undertaken to confirm the diagnosis. However, the clinching point in the given clinical scenario is the presence of a positive Gower’s sign.Gower’s sign is an excellent screening test for muscle weakness, which is typically observed as an early clinical feature of Duchenne muscular dystrophy (DMD).Creatinine kinase measurement is an easy and rapid test to aid in the diagnosis. Early diagnosis has significant implications not only for the child but for the family, particularly for genetic counselling. DMD is an X-linked recessive disorder, with an abnormal gene at the X chromosome at the Xp21 locus. It is a progressive degenerative muscular condition where muscle fibres are replaced by fat and fibrosis (i.e., become dystrophic).

Erythema Migrans is associated with Lyme disease, a tic transmitted infection caused by the spirochete Borrelia Burgdorferi. The rash usually appears at the bite site after 7 to 10 days. It is flat or slightly raised and migrates as the name suggests. Streptococcal throat infection and Crohn’s disease are both associated with erythema nodosum.Herpes simplex and Rheumatic fever may present with Erythema Multiforme and Erythema Marginatum respectively.

Diagnostic criteria of PCOsAccording to the American Association of Clinical Endocrinologists, at least two of three of the criteria below are required for diagnosis of PCOS after excluding other causes of irregular bleeding and elevated androgen levels.Hyperandrogenism (clinical or laboratory)Oligo- and/or anovulationPolycystic ovaries on ultrasoundDiagnosis of PCOS is possible without the presence of ovarian cysts.Rule out any other causes of hyperandrogenism and anovulation.Blood hormone levels:Testosterone (both total and free) or free androgen indexLH (LH:FSH ratio > 2:1)Oestrogen is normal or slightly elevated A clinical picture of hyperandrogenism overrules any normal hormone levels and can fulfil a diagnostic criterium of PCOS.

Complement activation plays a key role in the pathophysiology of SLE and it is recommended to continue monitoring serum levels of C3 and C4 to assess for disease activity. However, it is important to note that decreased serum complement is not consistently associated with disease flares.

Erythema nodosum is the most common type of inflammation of the subcutaneous fat tissue, referred to as panniculitis. Erythema nodosum appears as painful, erythematous round lumps, usually symmetrically on the anterior aspect of lower extremities. These lesions are self-limiting and tend to resolve within 2-8 weeks without undergoing necrosis or ulceration. There are various causes of erythema nodosum, but the most important among children is the streptococcal throat infection. Other causes include autoimmune conditions like sarcoidosis, inflammatory bowel disease, mycobacterial infection (TB), drugs like penicillin and sulphonamides, and malignancies like some leukemias and lymphomas.

Neuroanatomically, the frontal lobe is the largest lobe of the brain lying in front of the central sulcus. It is divided into 3 major areas defined by their anatomy and function. They are the primary motor cortex, the supplemental and premotor cortex, and the prefrontal cortex. Damage to the primary motor, supplemental motor, and premotor areas lead to weakness and impaired execution of motor tasks of the contralateral side. The inferolateral areas of the dominant hemisphere are the expressive language area (Broca area, Brodmann areas 44 and 45), to which damage will result in a non-fluent expressive type of aphasia.

Deaths by age group: 60% <1 year – due mainly to congenital, neonatal, and infection related problems.10% 1-4 years – due to accident (15%), cancer (15%), or congenital problems (14%)18% 15-19 years – accidental (42%) accidents reflect increased risk taking

Usage of inhaled corticosteroids are less associated with systemic adverse effects. However they are associated with local complications including dental caries and most commonly dysphonia.

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.