Correct Answer: B

Rationale: Weighing diapers is the most accurate way to estimate urine output in a child who is not toilet trained. This method provides a measurable and reliable estimate of fluid output.

Correct Answer: C

Rationale: Fever and general malaise are systemic signs of bacteremia, indicating that the infection may have spread beyond the local entry site. Localized pain, redness, and swelling are signs of a localized infection but do not necessarily indicate bacteremia.

Correct Answer: A

Rationale: The correct answer is A: Neuroblastoma. Neuroblastoma, a cancer that arises from nerve tissue, is associated with increased levels of catecholamine metabolites, including VMA and HVA, in the urine. Nephroblastoma (Wilms tumor) is a type of kidney cancer and is not typically associated with elevated levels of catecholamine breakdown products. Leukemia is a cancer of the blood and bone marrow and does not lead to increased VMA and HVA excretion in urine. Osteosarcoma is a bone cancer and is not linked to elevated levels of catecholamine metabolites in the urine.

Correct Answer: A

Rationale: Tachycardia is an early sign of shock as the body tries to maintain cardiac output in the face of declining circulatory volume. Blood pressure often remains normal until late in the progression, at which point decompensated shock is occurring.

Correct Answer: A

Rationale: Improvement in APIGN is indicated by an increase in urine output and a change in urine color from brown (due to hematuria) to a more normal appearance. This reflects a reduction in glomerular inflammation and improved kidney function. Choice B is incorrect because resting more comfortably is not a direct indicator of kidney function improvement. Choice C is incorrect because a decrease in appetite is not typically associated with improvement in APIGN. Choice D is incorrect because an increased BUN value would suggest worsening kidney function rather than improvement.