Table 2

Differential diagnosis: factors for and against each while radiological investigations were awaited

Differential diagnosisSupporting factorsFactors against
Infection
 Bacteraemia/viraemiaFever, raised inflammatory markers, low albumin level and raised white blood cell and neutrophil countsMultiple negative blood, CSF and urine cultures. No response to various antibiotics. Normal CXR. No murmur
 TB*Risk group, fever, history of coughQuantiferon equivocal, no family members affected, had BCG and scar and negative acid–alkali fast bacilli smear result
 Human immunodeficiency virusHepatosplenomegaly, developmental regression, faltering growth and feverLow-risk family, maternal antenatal screen negative, no risk procedures, negative polymerase chain reaction
 OsteomyelitisFever and swollen legOrganomegaly
Metabolic
 StorageHepatosplenomegaly, vacuolated lymphocytes, developmental regression and raised chitotriosidaseHigh fever, MPS and negative oligosaccharide screen result
Haematological
 Haemophagocytic lymphohistiocytosisHepatosplenomegaly and coagulopathyLack of bicytopenia or pancytopenia
 LCHLiver dysfunction and hepatosplenomegalyNo rash
Systemic inflammatory disorderFever, raised CRP and possible limb/joint involvementOrganomegaly and symptoms preceding fever