Hi and thanks for the query,
Being slim does not necessarily mean you got a disease but could simply be explained by genetic factors. However, the few symptoms you describe require that a cause of disease should be evaluated and excluded. Infectious disease, tumours, autoimmune diseases could explain all these. Blood tests, complete blood count
, markers of inflammation, immunoglobin E to ascertain the degree of the allergic levels, abdominal scan, liver
function tests, urine examination, a chest x ray
could be keys aspects for a complete evaluation. Consulting an internist first could be very useful.
Thanks and best regards,