Randi, a 24 year old, reports that "I have been urinating two to three times an hour, and it burns and itches and smells awful. My belly feels "yucky." When you ask Randi about pain, she states: "I don't have any pain at the back of my waist." Her temperature is 99.8°F. A clean voided urine sample is positive for leukocytes and the bacterium E. coli. Randi's UTI is most likely to be a(n):

A. Glomerulonephritis: This is an immune-mediated condition involving inflammation of the glomeruli and typically presents with proteinuria, hematuria, hypertension, and edema rather than urinary frequency, burning, or foul-smelling urine. The presence of E. coli and leukocytes does not support this diagnosis.

B. Kidney calculi: Kidney stones may present with flank pain, hematuria, and sometimes nausea or vomiting, but are not usually associated with urinary frequency, burning, or bacterial growth on urine culture. Randi’s symptoms point more toward an infectious etiology rather than a structural obstruction.

C. Lower UTI: cystitis (bladder infection) and possibly lower ureters: The burning, itching, frequent urination, and foul smell are classic signs of cystitis. The absence of flank pain and only a slightly elevated temperature further supports a lower tract infection rather than an upper one.

D. Upper UTI (pyelonephritis): Pyelonephritis typically presents with fever over 101°F, chills, nausea, vomiting, and significant costovertebral angle (CVA) tenderness or back/flank pain. Since Randi denies back pain and has only a mild temperature elevation, an upper UTI is unlikely.

McBurney's point is a specific location on the lower right quadrant of the abdomen that is used in diagnosing acute appendicitis. It is situated one-third of the distance from the right anterior superior iliac spine to the umbilicus.Tenderness at McBurney's point is a key clinical sign of appendicitis, often indicating that the inflammation has progressed beyond the appendix itself and is affecting the peritoneum.