^ The initial BCG reaction at 2 months of age may or may not be due to PTB exposure. It can also be due to how the BCG was injected. The reason why sa right singit nagkaroon ng enlarged lymph node is because doon nagdradrain ang lymph nodes from the BCG site niya sa right buttock. If sa right shoulder ang injection site, pwedeng sa axilla or sa neck area mag-enlarge ang lymph node. Treatment will consist of Isoniazid as your pedia prescribed.
How old is your daughter now? Did she undergo PPD recently to check for TB exposure? Did any of the household contacts undergo PPD testing as well?
Regarding your questions:
1. The ability to infect others depend on the response of the immune system of the exposed patient. For example, if the immune system recognized the TB mycobacteria and was able to "contain" the infection, then it was just exposure. This would result in a positive PPD test, negative chest x-ray.
TB mycobacteria cannot live on inanimate objects. Thus, you don't need to separate the spoon, fork, plate, etc. of the infected person. You also cannot get it from shaking hands with an infected person.
You need to be able to inhale the TB mycobacteria in order to get infected. You inhale it from getting coughed on, sneezed on, spit on by someone who is a close contact and with prolonged exposure. If the sputum or spit is left on the floor and not cleaned up right away, the TB mycobacteria can remain alive for about 9 to 10 hours and can infect people, especially if enclosed space (small room).
Close and prolonged exposure in order for you to get infected...
2. Usually if dormant TB (there is exposure plus active infection but no symptoms), meron ka ng findings sa x-ray. Eto yung mga asymptomatic patients na nalalaman lang na infected sila kapag nagpa-chest x-ray sila.
In order to infect people though, you have to be in the infectious stage (may symptoms na of coughing, etc. ) Pag nagpacheck ng AFB sputum smear, ang findings: positive AFB smear.
If exposure lang, no infection: Positive PPD test, negative chest x-ray
3. I think you would benefit from a consult with a pedia infectious disease specialist or a pedia pulmonologist.
Aside from the cough and the BCG reaction, are there any other symptoms that point to a possible TB infection?
The chest x-ray findings kasi point to pneumonia. Even the non-specific lymphadenopathy point to pneumonia since lymph nodes enlarge due to any infection.
If it is due to PTB, even with disappearance of the cough, lalabas pa rin ang lymphadenopathy kapag nag-repeat ng chest x-ray. If it was due to pneumonia, the lymphadenopathy will not be visible after a month or so...
At PGH: Dr. Liza Gonzales, Dr. Anna Liza Ong Lim (not sure if they have clinic at the UP FMAB)
At MDH: Dr. Melecia Velmonte (Room 402 if I am not mistaken)
At Cardinal Santos: Dr. Miguel Javier (Pedia pulmo, not sure of room)