A 56-year-old woman with systemic lupus erythematosus (SLE), who is maintained on prednisone 20 mg daily, presents for open right hemicolectomy for colon cancer. She is admitted to the surgical ICU postoperatively for refractory hypotension.
Which of the following is true regarding perioperative stress dose steroid supplementation?
Correct Answer: D
Patients with rheumatologic disease requiring long-term steroid supplementation for maintenance often exhibit secondary adrenal insufficiency, which may manifest as adrenal crisis during periods of perioperative stress. In the past, these patients may have indiscriminately received stress dose steroids, without preoperative risk stratification to determine which patients would benefit from such supplementation. Emerging literature suggests that it may even be safe to continue many patients’ baseline steroid dosage without supplementation for more minor procedures. Both the risk of secondary adrenal insufficiency and the level of surgical stress must be considered when determining which patients to administer stress dose steroids:
This type of surgery must also be considered, as the endogenous steroid secretion rate varies considerably between superficial (8-10 mg/d cortisol), minor (50 mg/d), moderate (75-150 mg/d), and major (75-150 mg/d) surgeries. Open abdominal surgery such as a colectomy qualifies as a moderate surgery, and thus this patient should receive stress dose steroid administration beginning preoperatively and continuing for at least the first postoperative day.
Hydrocortisone is the steroid of choice for stress and rescue steroid administration, given its relationship to endogenous cortisol. However, it is the glucocorticoid effect that is deficient in secondary adrenal insufficiency, and as doses rise, patients may experience adverse mineralocorticoid effects from high-dose hydrocortisone including edema, fluid retention, and hypokalemia. In these cases, it is reasonable to substitute a steroid with a higher relative glucocorticoid: mineralocorticoid activity, such as methylprednisolone or dexamethasone.
Which of the diffuse connective tissue disorders (DCTDs) has the highest rate of pulmonary involvement?
Correct Answer: B
Of the five DCTDs; SLE, SS, PM, DM, and RA, SS has the highest rate of pulmonary involvement, affecting up to 80% of patients. ILD and pulmonary arterial hypertension (PAH) are the most common features; together, these are the most common causes of death in SS, together accounting for up to 60%. ILD tends to affect patients with diffuse cutaneous sclerosis subtype, whereas PAH tends to affect patients with limited cutaneous sclerosis, though there is considerable overlap.
Aspiration due to incompetent lower esophageal sphincter and esophageal dysmotility may further complicate SS patients’ pulmonary function. Because of the importance of early treatment, monitoring with pulmonary function testing and high-resolution chest CT scan is recommended at regular intervals.
A 54-year-old woman with SLE, maintained on chronic prednisone, and complicated by stage III chronic kidney disease presents with acute anuric kidney injury.
Which of the following statements is most correct regarding this patient’s renal failure?
Lupus nephritis affects approximately 50% of patients with SLE and is a risk factor for both morbidity and mortality associated with SLE. Approximately 10% of patients with SLE go on to develop end-stage renal disease. As such, patients should be evaluated at the time of diagnosis and at least annually thereafter with a urinalysis and metabolic panel. When there is clinical evidence of renal impairment, a kidney biopsy is recommended. The most common type of renal involvement in SLE is immune complex–mediated glomerulonephritis. However, other types of injury including thrombotic microangiography and lupus podocytopathy may also occur.
The types of lupus nephritis are defined by the International Society of Nephrology/Renal Pathology Society (ISN/RPS) nomenclature. Depending on the class of injury, patients may benefit from potent immunosuppression with steroids and/or immunosuppressive agents. Traditionally, cyclophosphamide has been used, but increasingly mycophenolate mofetil and calcineurin inhibitors are being used with comparable or improved disease remission. Azathioprine, on the other hand, may increase disease relapse.
During an acute flare of lupus nephritis, it may be appropriate to re-biopsy to determine whether histology has changed in an effort to tailor therapy. Similarly, in patients who clinically respond to induction therapy, repeat biopsy will guide the required duration of maintenance therapy before a taper is started.
Which of the following is most consistent with a diagnosis of Takayasu arteritis (TAK)?
TAK is a large-vessel vasculitis affecting both adults and children; it is the most frequent cause of large vessel vasculitis in children. TAK causes intramural granulomatous inflammation of the aorta and its major branches, which are demonstrated as narrowing or stenosis on angiography of these vessels in the absence of atherosclerosis or fibromuscular dysplasia. The most common clinical presentations include malaise, weight loss, fever, headache, arthralgia, and claudication of the extremities; however, more acute presentations may include syncope, stroke, and aortic dissection. Clinical examination may reveal a discrepancy in systolic blood pressure between the limbs (present in 67% of patients in one series) and/or a bruit over the large arteries (present in 56% in one series). Pulmonary arteries are affected in 70% of cases, which may lead to pulmonary hypertension and/or pulmonary infarction.
Corticosteroids are the mainstay of remission induction, but approximately half of the patients require additional immunosuppression with either conventional or biologic DMARDs.
Morbidity and mortality from TAK are often because of ischemic complications of the large vessel involvement. Either surgical or endovascular revascularization is indicated to relieve critical, symptomatic stenoses, but these interventions are best undertaken during inactive disease. Acute therapy consists primarily of prompt immunosuppression to induce remission.
A 64-year-old gentleman with hypertension, hyperlipidemia, and mild asthma presents to the emergency department from home with massive hemoptysis. He is intubated for airway protection, and chest CT scan shows diffuse bilateral alveolar ground-glass opacities with inter- and intralobular thickening. He is admitted to the ICU where bronchoscopy and BAL is performed and consistent with diffuse alveolar hemorrhage (DAH). During his ICU course, he develops worsening acute renal failure with hematuria. Anti– glomerular basement membrane (anti-GBM) antibody is positive.
Which of the following statements is most likely correct regarding his disease?
Correct Answer: E
This patient’s pulmonary-renal syndrome is caused by anti-GBM disease, formerly known as Goodpasture disease, in which there is the presence of antibodies directed against the α3 chain of type IV collagen, found in the renal GBMs and the alveolar capillaries. Patients may present with glomerulonephritis, pulmonary hemorrhage, or both, but the most common manifestation is rapidly progressive renal failure.
Urinalysis in anti-GBM disease will show dysmorphic red cells, red cell casts, and proteinuria. Renal biopsy is necessary for confirmation of the disease and will show crescenteric glomerulonephritis and linear deposition of IgG along the GBM. When hemoptysis is present, chest x-ray may show bilateral alveolar infiltrates, greater in the perihilar areas and lower lobes. Chest CT is more sensitive and will detect ground-glass opacities, mainly in the middle lung fields.
Anti-GBM disease is caused by immune complex deposition, not a vasculitis. However, in up to 20% to 30% of patients with anti-GBM disease, patients may also have a positive ANCA.
Treatment of anti-GBM disease consists of high-dose steroids, cyclophosphamide, and plasmapheresis. Poor prognostic factors include >50% crescents on renal biopsy, serum creatinine >7 mg/dL, and requirement of renal replacement therapy within 72 hours of presentation.
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