Case summary
Male baby born at 37 weeks gestation following an uneventful pregnancy.
Antenatal screening was declined, but at birth there was phenotypic
suspicion of DS which was confirmed later by
fluorescence-in-situ-hybridization and karyotype. Jaundice within the
first 24-hours prompted a septic screen which demonstrated a high WCC of
107x109/l with a blast count of 80% . Flow
cytometry was consistent with TAM, and GATA-1 mutations were
subsequently identified.
Jaundice responded well to phototherapy and the patient was clinically
stable for the first 4 days of life, however on day 5, he developed
increased work of breathing requiring oxygen therapy. An echocardiogram
ruled out pericardial effusion but identified a large ventricular septal
defect (VSD) with moderately raised pulmonary pressures, possibly
contributing to the respiratory distress. Over the next 48-hours the WCC
rose to 152x109/l with concurrent hepatosplenomegly
and worsening respiratory distress despite diuretic therapy. The patient
commenced treatment with LDAC 1.5mg/kg once daily. A 7-day course was
well tolerated with the WCC falling to 40x109/l,
regression of hepatosplenomegaly and resolution of oxygen requirement
(Table 1).
Leucocytosis recurred 5 days after completion of LDAC with no infectious
cause identified and no improvement with antibiotics. Within 10 days of
LDAC, the WCC had risen to 102x109/l with 50% blasts,
hepatosplenomegaly had increased and respiratory distress had recurred
necessitating reintroduction of oxygen therapy. A second course of LDAC
was started but this required termination after 4 doses due to gut
toxicity with necrotising enterocolitis successfully managed
conservatively. The WCC did fall to 28x109/l but
within a week of stopping the second course of LDAC it had risen to
102x109/l, with worsening hepatosplenomegaly and an
increase in oxygen requirement, not due to deterioration in cardiac
status. A third course of LDAC was started 8 days after the second
course was prematurely terminated. This time a full 7-day course of LDAC
was well tolerated with the WCC falling to 16x109/l.
Seven days after completion of the third course of LDAC WCC had risen to
37x109/l, with increasing hepatosplenomegaly causing
further respiratory distress, thus a fourth LDAC course was commenced.
The WCC fell to 10x109/l following the fourth course
and respiratory support was no longer required a week after completion.
He has since been self-ventilating in air.
At age 5 months, three months after completion of the fourth course, the
WCC is normal at 8x109/l with normal haemoglobin,
platelet and neutrophil count. There is no palpable hepatosplenomegaly
and the patient has been able to establish feeding, is gaining weight
and developing normally.