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

The sinus venosus is a large quadrangular cavity which precedes the atrium on the venous side of the chordate heart. It exists distinctly only in the embryonic heart (where it is found between the two venae cavae)| however, the sinus venosus persists in the adult. In the adult, it is incorporated into the wall of the right atrium to form a smooth part called the sinus venarum, which is separated from the rest of the atrium by a ridge of fibres called the crista terminalis. The sinus venosus also forms the SA node and the coronary sinus.

The most worrying condition is testicular torsion and to exclude it exploratory surgery is required.

Syphilis is an infectious venereal disease caused by the spirochete Treponema pallidum. Syphilis is transmissible by sexual contact with infectious lesions, from mother to foetus in utero, via blood product transfusion, and occasionally through breaks in the skin that come into contact with infectious lesions. If untreated, it progresses through 4 stages: primary, secondary, latent, and tertiary.

The most probable diagnosis for this patient would be torsion of a hydatid cyst of the testis.Note:The differential diagnoses in acute testicular pain/swelling are listed in the possible answers. Testicular torsion typically affects adolescent males and presents with acute painful swelling and a horizontally lying testicle. Other options:- Epididymo-orchitis is diagnosed during surgery when a thickened erythematous epididymis is noted. Ectopic ureteric insertion into the vas must be excluded by ultrasound scan on an out-patient basis. The hydatid cyst or cyst of Morgagni represents the remnants of the Mullerian structure. In the pre-pubertal child, a surge in hormones can stimulate growth and chance of torsion. It is diagnosed by surgical exploration or by a blue dot sign. Idiopathic scrotal oedema tends to be within the scrotum itself, and the testis can be examined in the groin to exclude pain in the testis. All acute scrotal pain must be explored to exclude testicular torsion unless a surgical registrar is convinced of a torted hydatid cyst.- An 8-year-old is more likely to present with a torted hydatid cyst. The blue dot sign is diagnostic and can negate the need for surgical exploration. The age of the child also makes epididymo-orchitis less likely.- Idiopathic scrotal oedema presents with an erythematous and thickened scrotum. This can cross the midline and involve the whole scrotum.- Finally, an inguinal hernia would present with a mass in the groin extending to the scrotum that you cannot get above.

Scarlet fever is a childhood infectious disease caused by group A Streptococcus. It produces a papular rash, which is classically described as a sand-paper rash. The rash initially appears on the trunk, groin, and underarms and then spreads to extremities, usually sparing the palms and soles. Circumoral area is also spared, giving it pallor-like appearance. Diseases like erythema multiforme, contact dermatitis, staphylococcal scalded skin syndrome, and rubella produce a rash that classically affects the palms and soles.

The most obvious sign of a congenital cataract in a child less than 1 year would be a strabismus/squint. A 12 month old child is unable to complain of loss of visual acuity and the child is likely to see well in one eye ruling out clumsiness. Amblyopia may also be difficult to test at this age unless it presents with the strabismus. ‘White’ red reflexes usually only present in very mature congenital cataracts.

A 3-dimensional transoesophageal echocardiography (3D TEE) provides direct visualization of the entire PFO anatomy and surrounding structures. It allows more accurate diagnosis.

Gait variations in children are usually physiologically normal and only become a cause of concern when they persist or are associated with pain or other medical symptoms. Genu varus, also known as knock knees causes an outward rotation of the leg, leading the toes pointing outwards. The condition usually resolves by the age of 18 months. In comparison, in- toeing occurs with genu varus. Metatarsus adductus is also associated with an inward pointing of the toes.

Breast milk jaundice is thought to be associated with one or more abnormalities in the maternal milk itself. Breast milk jaundice syndrome generally needs no therapy if serum bilirubin concentrations remain below 270 mmol/l in healthy full-term infants. When the serum bilirubin concentration is above 270 mmol/l and rising, temporary interruption of breastfeeding may be indicated.