Hi,I sorry to hear you've been struggling with this,giving only inhaled steroids to a patient who has an upper respiratory infection will only prolong the infection,steroids act to suppress inflammatory immune response,which does nothing to get rid of pathogens it just reduces inflammation actually prolonging the infection if antibiotics aren't also used simultaneously.
I won't worry about firing anybody but this definitely should be evaluated further and treated by an Immunologist or a pediatric internist,and the Immunologist should have sent a report back to your primary explaining their findings so they know what's going on. The low IgG can definitely lead to chronic recurring upper respiratory infection. There are four subtypes of IgG 1,2,3,and 4,IgG2 deficiency being the one that causes the most problems in children especially if there is a simultaneous deficiency of IgA,to confuse stuff more there is four other types of immunoglobins other than IgG. There is also IgA,IgD,IgE and IgM,each having multiple subsets. So you can see why it's important to have someone who understands this stuff to treat it.
Immunoglobulins are antibodies produced by the immune system sort of like the security guards of the body and pathogens are the bad guys. These "security guards" remember what the bad guys look like and attach to them and call in the reinforcements,which are called killer T-cells. T-cells are what actually kill the pathogens. So if you don't have enough security guards looking out for the bad guys you have a situation. The most common pathogens in the upper respiratory tract of patients with IgG deficiency are usually Haemophilus influenzae type b,and Streptococcus pneumoniae.
Also it's important to know that infants don't have a fully developed immune system,IgG2 is not produced naturally until around age 2,which your son now is. The reason more than likely he didn't become sick until age 6 months is because IgG is the only immunoglobin that is permeable through the placenta,so you gave him some of your IgG when you were pregnant. This level of IgG2 wears of though around 6 months postpartum.
So in conclusion your son may soon start producing the missing IgG. Antibiotics are usually reserved for three weeks to give the immune system it's own time to fight off the infection,if after three weeks the infection is the same or worse,or in an emergency,then antibiotics are administered. There is also something called immunoglobulin therapy,were they intravenously inject immunoglobulins into the blood,giving a protection against recurring infection. But I think this is used more in older children and adults with a chronic Ig deficiency,but it's definitely worth mentioning to the immunologist.
There are some conditions that should be ruled out,such as:
X-linked agammaglobulinemia (usually there is a deficiency of IgA also)
Transient Hypogammaglobulinemia of Infancy (here also a IgA deficiency is present)
I hope all this babbling made some sense,and repost if need more info take care.
Hi: I don't know If it is my business,but I would find another doctor. I wouldn't wait, your child needs help, and only you know in your heart what he is going through. A good way to get research done is through google. Put the symptoms down may be you get lucky, I would take him to a children hospital ASAP. LOVE and LIGHT Elena