b. Has chronic primary renal failure

c. Has acute renal disease

d. Has chronic renal disease

The most probable answer to question 8 = option c.

Comments about answers:

a. Concentration of urine to this degree indicates that an adequate population of nephrons are functional to prevent primary renal failure. The small quantity of protein and high specific gravity indicate that primary renal failure and glomerulotubular imbalance are improbable.

b. See preceding comments in option a.

c. Detection of many granular casts is indicative of renal disease, even though urine concentration indicates that the disease is not of sufficient magnitude to cause renal failure. The large number of casts suggests (but does not prove) that the disorder is acute. The acute renal disease is associated with an inflammatory response.

d. This answer is possible; however answer c is probable. Additional information would be required to prove or disprove either answer.

e. Detection of granular casts is reliable evidence of tubular involvement in the inflammatory process. However, concurrent involvement of other portions of the urinary tract cannot be excluded.