Paediatrics for PRES Level 2

A 4-year-old boy is brought to the emergency department with a 2-day history of fever and a limp. He refuses to weight-bear on the right leg and holds the hip flexed and externally rotated. Temperature 38.7°C, CRP 88 mg/L, white cells 17 × 10⁹/L, ESR 62 mm/hr. What is the most important diagnosis to exclude?

1. Septic arthritis of the hip correct Correct. He meets multiple Kocher criteria: fever, non-weight-bearing, raised ESR and raised white cell count. Septic arthritis of the hip destroys the joint within days and requires urgent ultrasound, aspiration and surgical washout.
2. Perthes disease Wrong tempo. Avascular necrosis of the femoral head presents with insidious painless limp over weeks to months, without fever or raised inflammatory markers.
3. Juvenile idiopathic arthritis Possible in a limping child but usually more chronic, and it does not explain acute fever with a CRP of 88 in a two-day history.
4. Transient synovitis The commonest cause of a limp at this age and the main differential, but it is a diagnosis of exclusion. A child with fever, refusal to weight-bear and markedly raised inflammatory markers must not be labelled transient synovitis without excluding infection.
5. Slipped upper femoral epiphysis Wrong age group. It typically occurs in overweight adolescents around puberty, with the leg held externally rotated but without this acute febrile picture.

The point: Kocher criteria for septic arthritis of the hip: non-weight-bearing, fever above 38.5, ESR above 40, white cells above 12. The more criteria, the higher the probability. When in doubt, aspirate, a missed septic hip in a child is a catastrophic outcome.

Source: RCPCH / Irish paediatric guidance on the limping child RCPCH · tier 2, specialty society or college

A 6-month-old infant presents with three days of coryza followed by cough, wheeze and difficulty feeding. Respiratory rate 62, mild subcostal recession, oxygen saturation 93% in air, widespread fine crackles and wheeze. He is taking about half his usual feeds. What is the most appropriate management?

1. Nebulised salbutamol Wrong. Bronchodilators do not improve outcomes in bronchiolitis. The wheeze comes from small airway inflammation and plugging rather than from reversible bronchospasm.
2. Supportive care with attention to feeding and oxygenation correct Correct. This is bronchiolitis, usually respiratory syncytial virus. Management is supportive: monitoring, feeding support if intake falls, and oxygen if saturations drop below the accepted threshold. No drug has been shown to change the course.
3. Oral amoxicillin Wrong. It is a viral illness, and bacterial co-infection is uncommon.
4. Nebulised hypertonic saline Not recommended in current guidance. It has been extensively studied without convincing benefit on length of stay or outcome.
5. Oral prednisolone Wrong. Corticosteroids are not effective in bronchiolitis, in contrast to viral wheeze or asthma in older children.

The point: Bronchiolitis is supportive care. Know the admission thresholds: significant respiratory distress, apnoea, poor feeding at around half to three-quarters of normal intake, and persistent low saturations. Risk factors for severe disease include prematurity, congenital heart disease and chronic lung disease.

Source: NICE NG9 — Bronchiolitis in children: diagnosis and management NICE · tier 1, national regulator or guidance