Clinical Scenario:
A 25-week, 720-g infant has required prolonged parenteral nutrition through a central venous catheter because of severe intestinal dysfunction. On day 18, the infant develops temperature instability, lethargy and increasing oxygen requirement.
There is no obvious inflammation at the catheter site. Laboratory investigations show a rising CRP and thrombocytopenia. Blood cultures obtained simultaneously from a peripheral vein and the central catheter grow Candida species.
What is the most likely diagnosis?
A. Catheter thrombosis
B. IFALD
C. Metabolic bone disease
D. Catheter-related bloodstream infection
E. Essential fatty-acid deficiency
Correct answer & Complication:
Correct answer: D. Catheter-related bloodstream infection
Explanation
This is catheter-related bloodstream infection (CRBSI) associated with prolonged central venous access for PN.
The important exam clues are:
Central venous catheter + clinical deterioration + inflammatory markers + positive blood cultures from central and peripheral samples = CRBSI.
ESPGHAN specifically states that any child with intestinal failure and a central venous catheter is at significant risk of CRBSI. When suspected, paired blood cultures from the catheter and a peripheral vein should ideally be obtained simultaneously.
NICE recommends central venous access for neonatal PN in most circumstances, reflecting the need for reliable access for PN but also the importance of managing catheter-related complications.
Why the other options are wrong
- A. Catheter thrombosis: may cause catheter dysfunction or venous obstruction but does not explain Candida-positive blood cultures.
- B. IFALD: presents predominantly with conjugated hyperbilirubinaemia and liver dysfunction.
- C. Metabolic bone disease: is associated with prolonged nutritional deficiency and abnormal mineral metabolism, not acute sepsis.
- E. Essential fatty-acid deficiency: results from inadequate essential fatty-acid provision and has a different clinical presentation.
Reference
- ESPGHAN. Complications of Parenteral Nutrition (PN), Advice Guide. The guideline specifically addresses CRBSI diagnosis and recommends paired central and peripheral blood cultures.
- NICE NG154. Neonatal parenteral nutrition. NICE — Neonatal parenteral nutrition
