cont. the doctor has not taken any samples no cultures done. not only has my son

[Robyn]

had infections on his finger? but also has boils on his buttock and small white sores around his scrotum and penis area

[cowboydoc]

I would be vary suspicious of an internal infection. The boils and the small white sores on his nearby parts.
Your right, a sample should be taken unless the doctor was so sure of himself as to what these are. Cellulitius spreads like this along the fascia (the layers of skin) if it goes deep, then you have a real problem. Get him to a good doctor and make sure he does something, like lancing these.