hello..
you forgot to mention AGE
diabetes and BP history,menstrual history etc..
for klebsiella drug of choice is not nitrofurantion but as the symptoms are reduced probably it was acting..
are you sexually active..your partner can have bacteria with or wiwthout symptoms..so even partner has to be treated..
there are a lot of causes for susceptibility to infections..
do you experience any other symptoms apart form UTI?like generalised weakness or bruising or weight loss?
did you get any of blood tests done..?
if that is not the case get your blood work done for CBP, diabetes,
thyroid,liver function test,plasma
albumin etc..
USG of abdomen pelvis..etc
even though the workup is lengthy it helps you..
recurrent uti can be caused by stones or cyst in
kidney or transmission from partner,susceptibility to infections,etc..
had it been a case of susceptibility infections can occur in other areas of body which is not the case with you..
if you use any spermicidaal agents they have to be stopped and go for other methods of
contraception..
hope my answer helps you
if you have any more queries i would be happy to answer..