A 30 Year Old Man Visits Your Office With Complaints

A 30 year old man visits your office with complaints of an intense, sharp pain in his back and side. He admits to eating a diet high in animal proteins such as meat, cheese, and fish. Results of a complete urinalysis are:
Chemical/Physical Analysis
Color     Yellow     Glucose      Negative     Urobilinogen     Normal
Appearance     Clear     Protein     Small     Blood     Large
Specific Gravity     1.025     Ketones     150mg/dL     Nitrite     Negative
pH     5.0     Bilirubin     Negative     Leukocyte     Negative
Microscopic Analysis

>100 RBC/hpf
0-3 WBC/hpf
0-5 Squamous Epithelial Cells/hpf
Unidentified Crystals