WBR0372
| Author | [[PageAuthor::Rim Halaby, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Pathology |
| Sub Category | SubCategory::Renal |
| Prompt | [[Prompt::A 23 year old Caucasian female patient presents to the emergency department with a one day history of confusion and altered level of consciousness. Appropriate history could not be taken due to the patient’s condition. Patient’s vital signs are immediately taken. Her temperature is 39.5 degrees C (103.1 degrees F). Her heart rate is 102 beats per minute and her blood pressure is 90/50 mmHg. On physical examination, the patient has a petechial rash and nuchal rigidity. Blood cultures are taken and appropriate antibiotic therapy is immediately initiated. Blood cultures reveal group B Neisseria meningitidis. Patient’s condition gradually improves. Despite fluid resuscitation, the patient remains anuric. Abdominal computed tomography (CT) scan will reveal which of the following findings in this patient?]] |
| Answer A | AnswerA::Bilateral renal infarcts |
| Answer A Explanation | AnswerAExp::Bilateral renal cortical necrosis is characterized by renal infarcts. In is a rare complication of DIC, pregnancy, and sepsis, trauma, and drugs. |
| Answer B | AnswerB::Adrenal hemorrhage |
| Answer B Explanation | [[AnswerBExp::Adrenal hemorrhage followed by adrenal gland failure is characteristic of “Waterhouse-Friderichsen” syndrome. Although the syndrome is also commonly due to N. meningitidis, symptoms of adrenal insufficiency would be prevalent, such as abdominal pain, hypotension, hyponatremia, and hyperkalemia. The patient’s general status improvement without additional intervention and urinary findings favor bilateral renal cortical necrosis in this case.]] |
| Answer C | AnswerC::Shrunken kidney size bilaterally |
| Answer C Explanation | AnswerCExp::Shrunken kidney size bilaterally is a characteristic finding of chronic kidney disease (CKD). Given the patient’s acute history, shrunken kidneys are unlikely to be present on CT scan. |
| Answer D | AnswerD::Tubular eosinophilic casts that look like thyroid tissue |
| Answer D Explanation | AnswerDExp::Thyroidization of the kidney is a finding on renal biopsy that is commonly found in several chronic renal diseases. The process is characterized by renal tissue that resembles that of thyroid on renal biopsy under light microscopy. |
| Answer E | AnswerE::Dilation of renal pelvis and calyces |
| Answer E Explanation | AnswerEExp::Hydronephrosis is characterized by the dilation of renal pelvis and calyces. The patient’s presentation is not compatible with hydronephrosis |
| Right Answer | RightAnswer::A |
| Explanation | [[Explanation::Bilateral renal cortical necrosis is a rare phenomenon characterized by bilateral renal infarcts. It is a complication of vascular insult to the arteries that supply the renal cortex. Sepsis and disseminated intravascular coagulation (DIC) are typical inciting events. Pregnancy-related complications are frequently implicated in renal cortical necrosis as well. Other causes include drugs and trauma.
Contrast-enhanced computed tomography (CT) is the imaging of choice to diagnose renal cortical necrosis. CT scan reveals acutely hypo-dense areas in the renal cortex bilaterally. Renal replacement therapy is an effective therapy for many patients who suffer from renal cortical necrosis, but partial recovery is also possible. Educational Objective: Bilateral renal cortical necrosis is a rare complication of pregnancy-related medical conditions and sepsis. Contrast-enhanced CT scan is the imaging reveals bilateral renal infarcts that confirms the diagnosis. Reference: Chervu I, Koss M, Campese VM. Bilateral renal cortical necrosis in two patients with Neisseria meningitidis sepsis. Am J Nephrol. 1991;11(5):411-5 |
| Approved | Approved::No |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |