A 1-year-old boy presented to the emergency room with a 3-day history of fever, earache, and fatigue. A day before, he was seen in a walk-in clinic and was prescribed amoxicillin for acute otitis media.
The boy’s past medical history revealed a previously healthy infant of Southeast Asian descent. Pregnancy and delivery were normal. He had mild neonatal jaundice that did not require phototherapy. There was a history of anemia in the mother and maternal grandfather with no specific diagnosis.
On physical examination, the boy was noted to be pale and jaundiced. Axillary temperature was 37.8 degrees Celsius and heart rate was 130 beats per minute. Other vital signs including oxygen saturation (via pulse oximetry) were normal. His spleen could be felt at 6 cm below the left costal margin at the mid-clavicular line. He had evidence of increased pressure behind the left tympanic membrane with some enlarged lymph nodes in the ipsilateral cervical chains. The rest of the exam was unremarkable.
A complete blood count, differential, and chemical analysis was sent:
- Hb: 71 g/L (100-140)
- WBC: 22.9 x 10e9/L (5.0-15.0)
- Platelet: 960 x 10e9/L
- RBC: 4.79 x 10e12/L (3.5-5.0)
- Hematocrit: 23% (30-42)
- CV: 48.8 fL (74.0-108.0)
- MCH: 14.9 pg (24.0-31.0)
- MCHC: 306 g/L (320-365)
- Neutrophil: 7.73 x 10e9/L (1.5-8.5) with left shift
- Lymphocyte: 21.5 x 10e9/L (4.0-10.5)
- Reticulocyte count: 110 x 10e9/L
- Unconjugated bilirubin: 25 micromol/L (<17)
- Lactate dehydrogenase: 1870 U/L (500-920)
- Electrolytes: normal
Blood type, direct antiglobulin test, and cross match were requested.