Will a urinary tract infection show up on dipstick urine test?

Mostly. Nitrite reagent in dipstick works for most gram negative organisms, but does show gram positive bacteria like enterococcus, staphlococcus or streptococcus etc. Latter 2 are considered "skin" organisms but can be cause of utis in some, especially subjects on intermittent catheterization. Leucoocte esterase for wbcs in urine usually but, not always reliable. Urine culture is most reliable.