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.

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 days

Conditions 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.

Answer: Oculogyric crisis

Oculogyric crisis is an acute dystonic reaction of the ocular muscles characterized by bilateral dystonic elevation of visual gaze lasting from seconds to hours. This reaction is most commonly explained as an adverse reaction to drugs such as antiemetics, antipsychotics, antidepressants, antiepileptics, and antimalarials. Metoclopramide is a benzamide selective dopamine D2 receptor antagonist that is used as an antiemetic, with side effects that are seen frequently in children.1 The most common and most important side effects of metoclopramide are acute extrapyramidal symptoms, which require immediate treatment. Acute dystonic reactions occur as contractions of the muscles, opisthotonos, torticollis, dysarthria, trismus, and oculogyric crisis.

Standard deviation is defined as the measure of dispersion of a set of data from its mean. It measures the absolute variability of a distribution; the higher the dispersion or variability, the greater is the standard deviation and greater will be the magnitude of the deviation of the value from their mean.

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.

Hypopigmentation refers to a decrease in the amount of the pigment melanin in the skin, which leads to an abnormally lighter skin tone. Hypopigmentation can be generalized or localized. Generalized hypopigmentation occurs in albinism or can be ethnicity related. Causes of localized hypopigmentation include Incontinentia pigmenti, Lichen planus, Tuberous sclerosis, Piebaldism, vitiligo, and leprosy. Celiac disease is not associated with hypopigmentation.

Scabies is a dermatological condition caused by infestation of the Sarcoptes Scaibie. The tiny mite, often unseen by the naked human eye, is able to burrow into the stratum corneum where it lays its eggs, causing irritation and a rash related to the immune response against the mite and its eggs, saliva and faeces. On examination, the pathognomic small burrows are often seen on the skin along with small red papules and scratch marks; granulomatous nodules may also be seen especially in darker skin types. Other clinical subtypes such as bullous, and Norwegian (crusted) also exist. Common areas of infection include the hands, wrists, and the interdigital spaces. Infestation can also occur on the genital area, the buttocks, feet, ankles, flexor surfaces. First line treatment is with permethrin 5% dermal cream. It is important that all members of the household are also treated at the same time, and that contaminated bedding, clothes and furniture is adequately disinfected. Scabies is usually associated with overcrowded conditions.

The history is suggestive of a post-traumatic seizure which frequently occurs after moderate or severe traumatic brain injury. Although upgoing plantars can be identified in a post-ictal status, an intracranial bleed has to be excluded. A single seizure cannot be considered epilepsy

According to the Rumack-Matthew Normogram, accurate levels of paracetamol can be measured only between 4-15 hours. The levels measured before 4 hours post-ingestion would highly underestimate the level of paracetamol ingested.
The patient in question presents 2 hours after ingestion. Hence the most appropriate time to measure the levels of acetaminophen would be a further 2 hours later.

Other options:
– Note that the treatment with NAC can be delayed until the 4-hour level is obtained and compared to the nomogram.
– Furthermore, haemodialysis is only indicated if she develops hepato-renal syndrome that is likely to occur 72-96 hours post-ingestion.
– Indications for acute liver transplantation include persistent acidosis, hepatorenal syndrome and worsening coagulopathy.

H. pylori release the enzyme urease that has the ability to split urea releasing nitrogen. This process increases the pH in the gastric antrum making the gastric pH less acidic.

Helicobacter pylori:
It is a spiral, microaerophilic, gram-negative bacterium. It is one of the most common causes of antral gastritis in children. Ulcers are less common in children compared with adults; however, when they occur, they are more common in the duodenum.

The presence of H.pylori can be confirmed by:
– Stool antigen test (preferred)
– Serology
– Endoscopy with biopsy and culture
– Rapid urease tests

H.pylori gastritis may be associated with:
– Iron deficiency anaemia
– Gastric malignancy

Management:
The treatment is with triple therapy- two antibiotics, and an antacid.
Treatment failure is often attributed to a possible worldwide increase in macrolide resistance. Interestingly, children have higher antibiotic resistance compared with adults.

Note:
Zollinger-Ellison syndrome (ZES) causes gastrin-secreting tumours and can present as a part of multiple endocrine neoplasia type 1 (MEN1)- an autosomal dominant disorder.

The most probable diagnosis for this patient would be
Crohn’s disease.

Crohn’s disease:
An inflammatory bowel disease which can affect any part of the bowel from the mouth to the anus. Symptoms include abdominal pain, diarrhoea, pyrexia and weight loss.
Extra-intestinal manifestations include arthritis, uveitis, fatigue, anaemia and rashes including pyoderma gangrenosum and erythema nodosum.

Other options:
– Anorexia nervosa is an important diagnosis to consider. There are no indicators in the description that she has a fear of gaining weight or a strong desire to be thin.
– Diabetic ketoacidosis is incorrect because there is no polydipsia or polyuria. A patient in DKA is more likely to present with vomiting and not diarrhoea.
– Recurrent aphthous stomatitis is not a correct answer because it does not explain all of the symptoms described, only the mouth ulcers.
– Ulcerative colitis (UC) is also incorrect. UC is a form of inflammatory bowel disease that causes inflammation in the colon. The main symptom is bloody stools, which is not mentioned as a feature in history.

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. 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), and drugs like penicillin and sulphonamides. Coeliac disease is not linked with the formation of erythema nodosum.

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 swelling and bruising on the mandible needs to be checked for fractures. A facial X-ray can adequately visualize this.

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.

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.

NICE guidelines suggest that at the premonitory stage (pre-hospital) the patient should receive Diazepam 10−20 mg given rectally, or midazolam 10 mg given buccally. If seizures continue, the patient should receive lorazepam IV.

Tetralogy of Fallot usually is diagnosed after a baby is born, often after the infant has an episode of turning blue during crying or feeding (a tet spell). A loud heart murmur is usually present.

An atrial septal defect is present at birth, but many babies do not have any signs or symptoms.

Coarctation of the aorta is usually diagnosed after the baby is born. How early in life the defect is diagnosed usually depends on how mild or severe the symptoms are. New-born screening using pulse oximetry during the first few days of life may or may not detect coarctation of the aorta.
In babies with a more serious condition, early signs usually include:
pale skin
irritability
heavy sweating
difficulty breathing

Babies born with pulmonary atresia will show symptoms at birth or very soon afterwards. They may be cyanotic. However, it is not uncommon for a heart murmur to be absent right at birth.

CUTANEOUS DISORDERS OR DERMATOSIS ASSOCIATED WITH IBD
– Psoriasis
– Secondary amyloidosis
– Vitiligo
– Acquired epidermolysis bullosa

In some cases, non-granulomatous skin disorders occur as a reaction to the intestinal disease. These include:
– Pyoderma gangrenosum
– Neutrophilic dermatosis / Sweet syndrome, typically with pustules
– Pyodermatitis-pyostomatitis vegetans, a purulent erosive dermatosis characterised by snail-track ulcers
– Erythema multiforme
– Erythema nodosum
– Acneiform eruptions including nodulocystic acne, hidradenitis suppurativa and folliculitis
– Palisaded neutrophilic and granulomatous dermatitis
– Necrotizing and granulomatous small vessel vasculitis.

Infective endocarditis (IE) is an acute infective pathology of the endocardium secondary to some underlying cardiac pathology like VSD and TOF. Most commonly, it is bacterial in origin, caused by staphylococcus aureus in the majority of cases. Clinical features include fever, arthralgias, weight loss, anorexia, new-onset, or changing existing murmur. Skin manifestations include Osler’s nodes, Janeway lesions, splinter haemorrhages, and clubbing. Roth spots are conjunctival haemorrhages found in IE. Beau’s lines are not found in IE.

Many factors are related with the stimulation of bone formation and growth, the pubertal growth spurt, epiphyseal senescence, and fusion, including nutritional, cellular, paracrine, and endocrine factors. An important cellular factor in these processes is the differentiation and aging of chondrocytes in the growth plate. Important paracrine factors include the many molecular pathways involved in chondrocyte differentiation, vascularization, and ossification. Oestrogen and the GH-IGF-I axis are important endocrine factors.

Absence epilepsy is the most common type of generalized childhood epilepsies. It is mainly idiopathic, but 10-40% of the cases have a positive family history. It is characterized by frequent absence seizures and periods of unconsciousness. The hallmark of absence epilepsy on EEG is the bilaterally synchronous 2-4 Hz spike and wave discharges (SWDs). The average age of onset is around 4-8 years, being more prevalent among girls. Treatment resistance is not common.

The clinical presentation of lichen planus has several variations, as follows:
– Hypertrophic lichen planus
– Atrophic lichen planus
– Erosive/ulcerative lichen planus
– Follicular lichen planus (lichen planopilaris)
– Annular lichen planus
– Linear lichen planus
– Vesicular and bullous lichen planus
– Actinic lichen planus
– Lichen planus pigmentosus
– Lichen planus pemphigoides

Intussusception is a condition in which one segment of intestine telescopes inside of another, causing an intestinal obstruction. Although intussusception can occur anywhere in the gastrointestinal tract, it usually occurs at the junction of the small and large intestines. Most describe the symptoms of intussusception as a triad of colicky abdominal pain, bilious vomiting, and currant jelly stool. The primary symptom of intussusception is described as intermittent crampy abdominal pain.

Total parenteral nutrition (TPN) frequently causes derangement of liver function in children.

Other options:
– While line sepsis and thromboembolism are recognised complications of TPN, they do not occur frequently.
– A child who is on TPN will require regular blood tests because of the potential for the development of electrolyte abnormalities. Need to observe their liver function, in order to provide TPN more accurately.

The physical features and developmental delay are the key aspects in the given scenario.
The child in question shows features of gross motor and social developmental delay and has physical features indicative of Prader-Willi syndrome (hypopigmentation, esotropia, disproportionately small hands and feet, loss of central muscle tone and undescended testes).

Children with Prader-Willi syndrome can present with failure to thrive until ,12-18 months, at which point, hyperphagia and obesity become more prominent.

Other options:
– Although Klinefelter syndrome can present with delayed development, undescended/small testes and reduced muscle power, the presence of small hands/feet, hypopigmentation and failure to thrive are not characteristic features.
– Marfan syndrome presents with different physical features (arachnodactyly, cardio-respiratory complications and skin changes, amongst others) than those associated with Prader-Willi syndrome.
– DiGeorge can manifest with developmental delay, hypotonia and feeding difficulties. However, this clinical scenario does not report any of the typical facial features, hearing abnormalities or cardiac abnormalities that are typically caused by DiGeorge syndrome.
– Russell-Silver syndrome can cause developmental abnormalities, poor muscle tone and power (poor head control and muscle function), feeding difficulties and poor growth during the post-natal period and infancy. However, characteristic facial (small, triangular face, blue sclerae) and skeletal abnormalities (limb asymmetry, finger abnormalities) are not present. Therefore, Prader-Willi syndrome is the most appropriate diagnosis for this patient.

Note:
Prader-Willi syndrome is an example of genetic imprinting where the phenotype depends on whether the deletion occurs on a gene inherited from the mother or father:
In Prader-Willi syndrome, it is the paternal gene that is deleted from the long arm of chromosome 15, while in Angelman syndrome the maternal gene is deleted.
Prader-Willi syndrome can occur due to the microdeletion of paternal 15q11-13 (70% of cases) maternal uniparental disomy of chromosome 15.

Puberty is a period of transitioning into adulthood by developing full reproductive potential by undergoing drastic physiological and psychological changes. For boys, it occurs around 9-16 years of age typically. The process of pubertal changes is usually divided into stages called tanner’s stages. The physiologic changes of puberty are initiated by the release of gonadotropin-releasing hormones from the hypothalamus, which then interact with numerous endogenous and environmental stimuli to bring about the physical pubertal features.
Tanner stage 2 in boys is characterized by the thinning and reddening of the scrotal skin.
The growth spurt of around 9cm per year is expected in boys, at the peak velocity.
Testicular enlargement of >3cm commences puberty.
Pubarche, in the absence of other secondary sexual characteristics, is pathological.
Adrenarche is the increase in the secretion of adrenal androgens, occurring prior to increased gonadotropin release.

Although WPW syndrome is a type of supraventricular re-entrant tachycardia, CCBs are contraindicated in its management. This is because CCBs depress AVN conduction; the current then passes through the accessory pathway (bundle of Kent) instead, causing ventricular tachycardia.

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

Internal abdominal bleeding is most probably the cause of the child’s shock, especially unresponsive to fluid boluses.