History of recurrent infections and failure to thrive (probably due to pancreatic enzyme insufficiency) is highly suggestive of cystic fibrosis. Pseudomonas has been identified as an important respiratory pathogen in patients with cystic fibrosis.

Based on the clinical scenario, the most probable diagnosis is acute appendicitis.Acute appendicitis presents typically with central abdominal pain migrating to the right iliac fossa, anorexia, nausea and fever. The temperature usually does not go beyond 40C. Although appendicitis is a clinical diagnosis, an ultrasound scan showing an appendix width of greater than 6mm is diagnostic.Pyrexia, guarding, and pain are all in keeping with appendicitis.Other options:- Cholecystitis is very rare in children, and although gall stones are present, there is no jaundice or biliary tree dilatation suggested by the scan.- Impacted Gall Stone: There is no mention of common bile duct dilatation in the clinical scenario.- Sickle Cell Crisis: A sickle cell crisis should not cause guarding, or an ultrasound scan finding of a dilated appendix base.- Gastroenteritis: Gastroenteritis would not produce the ultrasound scan findings described above with a thickened appendix.

Relative risk is the probability of an outcome occurring in an exposed group as compared to the probability of that outcome in an unexposed group. In the scenario given, 50% of the children exposed developed the disease while only 10% of the children who were unexposed developed the disease. The relative risk was therefore 50/10=5. There is no further information about whether the study was controlled, the confidence interval, or the type of study. It therefore cannot be confirmed whether the chemical is causative and if it should be avoided.

Among the given options, the most likely cause for the patient’s presenting symptoms is acute interstitial nephritis secondary to anti-tubercular therapy (ATT)Drug-induced acute interstitial nephritis can occur following treatment with beta-lactams, sulphonamides, rifampicin, ethambutol, and erythromycin. They can cause an acute allergic reaction with the infiltration of immune cells.Acute interstitial nephritis is said to be the most common renal complication in patients undergoing anti-TB treatment. Rifampicin is the most implicated drug, although ethambutol can also be a cause. The pathogenesis involves an immune-complex mediated acute allergic response, which leads to their deposition on renal vessels, the glomerular endothelium, and the interstitial area. Other options:Isoniazid does not affect the kidneys. Pulmonary-renal syndrome is a feature of Goodpasture’s syndrome. It is characterized by renal failure and lung haemorrhage. Severe cardiac or renal failure ensues and is complicated by pulmonary oedema, systemic lupus erythematosus, Henoch-Schönlein purpura, and cryoglobulinemia.

Jaundice is considered pathologic if it presents within the first 24 hours after birth. Although up to 60 percent of term new-borns have clinical jaundice in the first week of life, few have significant underlying disease.1,2 However, hyperbilirubinemia in the new-born period can be associated with severe illnesses such as haemolytic disease, metabolic and endocrine disorders, anatomic abnormalities of the liver, and infections. The risk factors here is the mothers blood ground which suggests the cause is fetal-maternal blood group incompatibility.

This girl most likely has Turner syndrome (TS) also known as 45,X, a condition in which a female is partly or completely missing an X chromosome. Signs and symptoms vary among those affected. Often, a short and webbed neck, low-set ears, low hairline at the back of the neck, short stature, and swollen hands and feet are seen at birth. Typically, they are without menstrual periods, do not develop breasts, and are unable to have children. Heart defects, diabetes, and low thyroid hormone occur more frequently. Most people with TS have normal intelligence. Many, however, have troubles with spatial visualization such as that needed for mathematics. Vision and hearing problems occur more often. Turner syndrome is not usually inherited from a person’s parents. No environmental risks are known and the mother’s age does not play a role. As a chromosomal condition, there is no cure for Turner syndrome. However, much can be done to minimize the symptoms including prescribing growth hormone, either alone or with a low dose of androgen, and oestrogen replacement therapy which is crucial long term for maintaining good bone integrity, cardiovascular health and tissue health

Children are very prone to dehydration during an episode of gastroenteritis. Dehydration is detected early by increased capillary filling time.

Precocious puberty is the attainment of normal pubertal biochemical and physical features at an abnormally early age. The age cut-offs commonly used to define precocious puberty are 8 years for females and 9 years for males. Precocious puberty may be central (true) or peripheral (false) based on the aetiology. Central precocious puberty is due to the premature activation of the hypothalamic-pituitary-gonadal axis, which in turn leads to the development of secondary sexual characteristics at an earlier than usual age. Central precocious puberty is mostly idiopathic, but other causes include congenital or prolonged, untreated hypothyroidism, congenital or acquired central nervous system pathologies, and several genetic syndromes like Silver-Russell syndrome. The other mentioned choices cause peripheral or false precocious puberty.

The thymus is a lymphoid organ located in the anterior mediastinum. In early life, the thymus is responsible for the development and maturation of cell-mediated immunologic functions. The thymus is composed predominantly of epithelial cells and lymphocytes. Precursor cells migrate to the thymus and differentiate into lymphocytes. Most of these lymphocytes are destroyed, with the remainder of these cells migrating to tissues to become T cells.DiGeorge’s syndrome (DGS) is a developmental abnormality affecting the thymus. The classic triad of features of DGS on presentation is conotruncal cardiac anomalies, hypoplastic thymus, and hypocalcaemia (resulting from parathyroid hypoplasia).

Tooth extraction or any surgical procedure may introduce bacteria into the blood stream. The most commonly involved organisms include Staphylococcus aureus and Streptococcus viridans. Once in the blood, these organisms have a very high tendency of attaching to the walls of the heart and causing inflammation known as endocarditis.

When topical agents are insufficient or not tolerated, or in cases of moderate to severe acne, especially when the chest, back and shoulders are involved, systemic antibiotics are often considered the next line of treatmentSystemic antibiotics should not be used to treat mild acne because of the risk of increasing resistance. The additional use of nonantibiotic topical agents in combination with oral antibiotics should be considered. Topical retinoids with oral antibiotics may give a faster response and be more effective than either drug used alone.Treatment with tetracyclines and erythromycin reduces P. acnes within the follicles, thereby inhibiting the production of bacterial-induced inflammatory cytokines. These agents also have inherent anti-inflammatory effects, such as suppressing leukocyte chemotaxis and bacterial lipase activity.

The most probable cause for the patient’s presenting symptoms is encephalitis secondary to measles infection.Encephalitis:Encephalitis occurs in 1 per 1000 measles cases. It usually presents within 1–14 days of the rash, usually day 5. It may present with fever, headache, vomiting, stiff neck, meningeal irritation, drowsiness, seizures, reduced consciousness| 15% will have neurological sequelae| 10% mortality.Other options:- Acute disseminated encephalomyelitis occurs in 1 per 1000 measles cases. It is thought to be a postinfectious immune response. Clinical manifestations include fever, headache, neck stiffness, seizures and mental status changes. It could fit this presentation although it tends to present in the recovery phase of measles infection, typically two weeks after the exanthem. In contrast, encephalitis tends to occur within a few days of the rash.- The history is not that of a typical febrile seizure as it lasted >15 minutes. He has also not recovered consciousness at 4 hours. The diazepam should have been eliminated within 4 hours and so should no longer be contributing to his reduced level of consciousness. Also, the history states the recent diagnosis of measles, and so complications of measles should be considered.- Intracranial bleed secondary to thrombocytopenia: Measles is not known to cause thrombocytopenia.- Subacute sclerosing panencephalitis (also known as Dawson’s encephalitis): This is an extremely rare complication of measles. It is a progressive degenerative disease of the central nervous system that occurs 7–10 years after a measles infection. The treatment for SSPE is mainly intraventricular interferon therapy through an Ommaya reservoir. The prognosis is poor, and it is usually fatal.

Human breast milk composition is best suited to meet all the growth and development requirements of a baby. It contains numerous biochemicals ranging from macronutrients, micronutrients, minerals, immunoglobulins, inflammatory markers, and growth factors. The major bioactive factors found in human breast milk are: immunoglobulins (IgA, IgG, and IgM), cells (macrophages and stem cells), growth factors (epidermal growth factor, tumour necrosis factor-alpha, transforming growth factor-beta, and vascular endothelial growth factor), cytokines, chemokines, hormones, metabolic hormones, glycans, and mucins.

The most likely causative organism for the symptoms of this child is Giardia lamblia.Giardiasis results in fat malabsorption thus giving rise to greasy stools. It is resistant to chlorination, hence has a risk of transfer in swimming pools.World Health Organisation definitions- Diarrhoea: > 3 loose or watery stool per day- Acute diarrhoea < 14 days- Chronic diarrhoea > 14 daysConditions that usually present as acute diarrhoea:- Gastroenteritis: It may be accompanied by abdominal pain or nausea/vomiting.- Antibiotic therapy: Can occur following antibiotic therapy, especially common with broad spectrum antibiotics.Conditions that usually present as chronic diarrhoea:- Irritable bowel syndrome: It is a very common disease.The most consistent features are abdominal pain, bloating and change in bowel habit. Patients may be divided into those with diarrhoea predominant IBS and those with constipation-predominant IBS.Features such as lethargy, nausea, backache and bladder symptoms may also be present in these patients.- Ulcerative colitis: It presents as bloody diarrhoea. Patients can also present with crampy abdominal pain and weight loss. Faecal urgency and tenesmus may be seen.- Crohn’s disease: It is also associated with crampy abdominal pains and diarrhoea. Bloody diarrhoea less common than in ulcerative colitis. Other features include malabsorption, mouth ulcers perianal disease and intestinal obstruction – Colorectal cancer: It is very rare in children. The symptoms depend on the site of the lesion but include diarrhoea, rectal bleeding, anaemia and constitutional symptoms like weight loss and anorexia.- Coeliac disease: In children, it may present with failure to thrive, diarrhoea and abdominal distension.Other conditions associated with diarrhoea include thyrotoxicosis, laxative abuse, appendicitis, and radiation enteritis.

Among the given options, psoriasis is not associated with hypertrichosis.The causes of hypertrichosis include:- Drugs: minoxidil, ciclosporin, and diazoxide.- Congenital hypertrichosis lanuginosa and congenital hypertrichosis terminalis.- Porphyria cutanea tarda- Anorexia nervosa

Congenital hypothyroidism is one of the most important diseases of the new-born, which may lead to mental and physical retardation when treatment is delayed or an appropriate dosage of thyroxine is not administered. The most alarming and earliest sign is jaundice, especially when it is prolonged, during the neonatal period.

Undescended testis (UDT) is a common abnormality, affecting about 1/20 males at birth. Half of these have delayed testicular descent, with the testis in the scrotum by 10-12 weeks after term. Beyond this spontaneous descent is rare. Current treatment recommendations are that UDT beyond 3 months need surgery between 6-12 months of age. Some children have scrotal testes in infancy but develop UDT later in childhood because the spermatic cord does not elongate with age, leaving the testis behind as the scrotum moves further from the groin. The maldescended testis suffers heat stress when not at the lower scrotal temperature (33 degrees Celsius), interfering with testicular physiology and development of germ cells into spermatogonia. Recent evidence suggests orchidopexy between 6-12 months improves germ cell development, with early reports of improved fertility, but no evidence yet for changes in malignancy prognosis.Hypospadias is also a common abnormality in new-born males, affecting about 1/150 boys. Androgens control masculinization of the genital tubercle into penis between 8-12 weeks’ gestation, with tabularization of the urethra from the perineum to the tip of the glans. If this process is disrupted hypospadias occurs, with a variable proximal urethral meatus, failed ventral preputial development producing a dorsal hood, and discrepancy in the ventral versus dorsal penile length, causing a ventral bend in the penis, known as chordee. Surgery to correct hypospadias is recommended between 6-18 months.

Cystic fibrosis has an autosomal recessive pattern of inheritance, meaning that a person might be a carrier of the disease without developing it. If the unaffected partner is a carrier, then there is a 50% chance of inheritance and a 50% chance of having a child who is a carrier. However, if the partner is not a carrier, the offspring will not develop the disease but the possibility of being a carrier raises up to 100%.

Developmental milestones at 4 months of age:Social and Emotional:Smiles spontaneously, especially at people Likes to play with people and might cry when playing stops Copies some movements and facial expressions, like smiling or frowningLanguage/CommunicationBegins to babble Babbles with expression and copies sounds he hears Cries in different ways to show hunger, pain, or being tiredCognitive (learning, thinking, problem-solving)Lets you know if he is happy or sad Responds to affectionReaches for a toy with one hand Uses hands and eyes together, such as seeing a toy and reaching for it Follows moving things with eyes from side to side Watches faces closely Recognizes familiar people and things at a distance Movement/Physical DevelopmentHolds head steady, unsupported Pushes down on legs when feet are on a hard surface May be able to roll over from tummy to back Can hold a toy and shake it and swing at dangling toys Brings hands to mouth When lying on stomach, pushes up to elbows

6 month old babies that go through normal developmental milestones, should enjoy playing with others and especially their parents.The other milestones are expected of a 9-month-old.