Ans. a (Fanconi's anemia) (Ref. Nelson Textbook of Pediatrics, 19th ed./Ch. 489)Neutropenia may be present with some viral infections, particularly parvovirus B19 infection; drug reactions; systemic lupus erythematosus; typhoid; brucellosis; and infiltrative diseases of the bone marrow, including lymphoma, leukemia, tuberculosis, and histoplasmosis.The rash of erythema infectiosum (fifth disease), which is caused by human parvovirus B19, primarily affects children 3 to 12 years old; it develops after fever has resolved as a bright blanchable erythema on the cheeks ("slapped cheeks") with perioral pallor.Educational point:# Earliest feature of Fanconi's anemia is pancytopenia.# Filgastrim is drug used in Rx of febrile neutropenia.