Most likely etiology in 10 month old child with high grade fever since 7 days, with the following x-ray finding and not responding to ceftriaxone
Streptococcus pneumoniae and staphylococcus aureus both can lead to consolidation of a lobe of lung as seen in the Chest x-ray. But Resistance to Ceftriaxone is seen in staphylococcus aureus only.
Streptococcus pneumoniae
Staphylococcus aureus
Mycoplasma
Respiratory Syncytial Virus