1 Infection: Blood in the urine can be a sign of urinary tract infection (UTI). An infection can be present in the lower urinary tract (bladder and urethra) or higher in the urinary tract (kidneys or ureters).  Nephrolithiasis: Kidney or bladder stones may form inside the urinary tract and can cause bleeding into the urine.
From 12 November 2015, however, if a person with at least 12 months of permanent residence wishes to apply for British citizenship he or she first has to apply for a permanent residence certificate or card. This change was introduced by the British Nationality (General) (Amendment No. 3) Regulations 2015 (SI 2015/1806).
Permanent residents must present their I-551 Permanent Resident Card when entering the United States. A passport is not required to enter the US, but you may need one to enter Mexico, depending on your nationality. A passport is the best form of international identification and having one may help you avoid hassles when crossing borders.