Neonatal jaundice — structured SAQ (15 marks)

(a) Classification (2 marks)

One mark for the classification, one for the rationale. ^[1][3]

• Pathological, unconjugated, haemolytic jaundice of immune origin (Rh isoimmunisation). Onset within the first 24 hours, a rapid rise (over 12 micromoles per litre per hour), a positive direct antiglobulin test and a reticulocytosis all confirm an immune haemolytic process.
• The classification matters because it places this infant on the lower (risk-factor) threshold line of the nomogram, not the standard line.^[1]

(b) Initial management and threshold framework (4 marks)

One mark per named step. ^[1][2]

• Plot the bilirubin against postnatal age in hours on the gestational-age-stratified nomogram (AAP 2022 / NICE CG98 / Queensland Clinical Guidelines), applying the lower risk-factor threshold line because of haemolysis. A single number without the timing and the nomogram is meaningless.^[1]
• Intensive phototherapy now. The bilirubin is at the phototherapy threshold with haemolysis and a rapid rise; intensive phototherapy with high irradiance and a close light source is the first intervention.
• Hydration, warmth and feeding — phototherapy increases insensible losses; supplement feeding as needed; keep the infant warm.^[3]
• Recheck the bilirubin within 2 to 3 hours of starting phototherapy to confirm the trajectory is falling.^[1]

(c) Investigations to confirm the underlying cause (3 marks)

One mark per investigation. ^[1][3]

• Maternal blood group and antibody screen, infant blood group and direct antiglobulin test — confirms immune haemolysis and identifies the antibody.
• Full blood count with reticulocyte count — reticulocytosis confirms active haemolysis; haemoglobin trajectory guides transfusion decisions.
• G6PD assay — coexisting G6PD deficiency changes both the trajectory and the trigger avoidance advice.^[3]
• Albumin — a low albumin (under 30 g per litre) lowers the threshold and supports the case for exchange.

(d) Continued rise despite intensive phototherapy (3 marks)

One mark per step. ^[1][5]

• Intravenous immunoglobulin — indicated in immune-mediated haemolysis when the bilirubin continues to rise despite intensive phototherapy, with the aim of reducing the exchange rate.^[1]
• Prepare for exchange transfusion. Indicated if the bilirubin reaches the exchange threshold despite intensive phototherapy and IVIG, or at the first sign of acute bilirubin encephalopathy (lethargy, hypertonia, high-pitched cry).^[1]
• Acknowledge complications of exchange — thrombocytopenia, electrolyte disturbance, necrotising enterocolitis, and serious adverse events in a small minority; the decision is reserved for genuine threshold-crossing, not for marginal elevation.^[5]

(e) Communication (3 marks)

Scored against the rapport and communication domains. ^[1]

• Plain language, no jargon: "Your baby's blood type and yours are not compatible in a way that has caused some of his red cells to break down faster than usual. That makes a substance called bilirubin, which is what makes him yellow. We are treating him with special lights to bring the level down. If the level keeps rising, we have other treatments ready."^[1]
• Acknowledge fear directly: "I know the word 'brain damage' is frightening. We are watching his level very closely and treating aggressively to keep it in a safe range. We will keep you informed at every step."
• Commit to a follow-up plan, a named person to ask questions of, and a debrief once the picture stabilises.