Which lab result would be consistent with a diagnosis of rheumatoid arthritis?

Choice A reason: Crush injuries release myoglobin from damaged muscles, causing rhabdomyolysis. Myoglobin precipitates in renal tubules, obstructing them and leading to acute tubular necrosis, an intra-renal acute kidney injury. This toxic effect, combined with oxidative stress, impairs filtration, making this statement accurate for the pathophysiology of renal injury.

Choice B reason: Large IV fluid volumes are used to prevent renal injury in rhabdomyolysis by diluting myoglobin and maintaining perfusion. Fluid overload may cause pulmonary edema but does not typically cause pre-renal damage, which results from hypoperfusion. This statement is inaccurate, as fluids are protective, not harmful.

Choice C reason: Pain medications like NSAIDs can be nephrotoxic, causing intra-renal damage by reducing renal blood flow or causing interstitial nephritis. However, pre-renal damage results from hypoperfusion, not direct toxicity. In crush injuries, myoglobin is the primary cause, making this statement less accurate than myoglobin-related tubular damage.

Choice D reason: Significant blood loss causes pre-renal injury by reducing renal perfusion, not post-renal damage, which involves urinary obstruction. Crush injuries primarily cause intra-renal damage via myoglobin. This statement is inaccurate, as it misattributes the mechanism and type of renal injury in this context.

Choice A reason: Achieving euthyroid state before hyperthyroidism procedures, like thyroidectomy, aims to normalize thyroid hormone levels, not prevent hypothyroidism. Post-procedure hypothyroidism is a separate concern managed with hormone replacement. This statement is inaccurate, as the primary goal is to stabilize metabolism, not prevent low thyroid function.

Choice B reason: Medications like methimazole or propylthiouracil are used pre-procedure to achieve euthyroid state, reducing thyroid hormone levels to prevent thyroid storm—a life-threatening hypermetabolic crisis triggered by surgery or stress. This statement is accurate, as stabilizing thyroid function minimizes perioperative complications like tachycardia or hyperthermia.

Choice C reason: Euthyroid state does not directly enhance the efficacy of anti-thyroid medications but rather prepares the patient for surgery by reducing hyperthyroid symptoms. Medications are effective independently, and this statement is inaccurate, as the rationale focuses on patient safety, not drug potentiation.

Choice D reason: While euthyroid state reduces metabolic stress, it does not primarily minimize bleeding risk. Bleeding is managed through surgical techniques and coagulation status, not thyroid hormone levels. This statement is inaccurate, as bleeding risk is not the primary concern addressed by achieving euthyroid state pre-procedure.