83. Systemic Lupus Erythematosus
Definition
Systemic lupus erythematosus (SLE) is a chronic, generalized, multifaceted inflammatory disorder that can affect every organ. SLE is categorized as an autoimmune disease characterized by autoantibody formation, producing multisystem microvascular inflammation.
Incidence
In the United States the average incidence of SLE is about 1:10,000. The incidence varies with ethnicity. The female:male ratio ranges from 8:1 to 10:1. Internationally the incidence is variable by country and ethnicity (see the table below).
Etiology
The specific cause of SLE has not yet been elucidated. There are suspected causes, including immune system dysregulation as well as immune complex tissue damage—particularly in the skin and kidneys. Development of SLE may result from multiple immune disturbances. In addition, 10 gene loci have been implicated in increased risk of development of SLE.
American College of Rheumatology Systemic Lupus Erythematosus Diagnosis Criteria
This is called the SOAP BRAIN MD mnemonic:
| Serositosis | Pleurisy, pericarditis |
| Oral ulcers | Oral or nasopharyngeal, usually painless; the palate is most specific |
| Arthritis | Nonerosive, Jaccoud-type |
| Photosensitivity | Unusual skin reaction to light exposure |
| Blood disorders | Leukopenia, lymphopenia, thrombocytopenia, positive result of Coombs-test for anemia |
| Renal involvement | Proteinuria (>0.5 g/day) |
| Antinuclear antibodies (ANAs) | Higher titers generally more specific (>1:160) |
| Immunologic phenomena | Lupus erythematosus (LE) cells; anti–double-stranded DNA (dsDNA); anti-Smith (Sm) antibodies; antiphospholipid antibodies; lupus; anticoagulants |
| Neurologic disorder | Seizures or psychosis |
| Malar rash | Fixed erythema over the cheeks and nasal bridge |
| Discoid rash | Raised rimmed lesions that have keratotic scaling and follicular plugging |
Signs and Symptoms
• Alopecia
• Anasarca
• Aseptic meningitis
• Bullous lesions
• Crackles
• Diffuse intrapulmonary hemorrhage
• Dysrhythmias
• Effusions
• Fever
• Fibromyalgia
• Focal neurologic deficits
• Gross hemoptysis
• Heart failure
• Hematuria
• Hypertension
• Hypoxia
• Infectious endocarditis
• Inflammatory myocarditis
• Ischemia
• Jaccoud arthropathy/arthritis/syndrome
• Libman-Sacks disease (atypical verrucous endocarditis)
• Lymphadenopathy
• Malar rash
• Mesenteric vasculitis
• Mononeuritis
• Myositis
• Oral ulcers
• Organic brain syndrome (currently defined as delirium, dementia, and amnestic and other cognitive disorders; mental disorder from general medical condition; and substance-related disorder)
• Palatal ulcers
• Pancreatitis
• Panniculitis
• Periorbital edema
• Peripheral edema
• Peritonitis
• Photosensitive rash
• Plaque-like lesions with follicular plugging
• Pleuropericardial friction rubs
• Pneumonitis
• Psychosis
• Pulmonary embolism
• Raynaud phenomenon
• Seizures
• Splenomegaly
• Tachypnea
• Urticaria
• Vasculitic purpura
Medical Management
Treatment of SLE is not curative; rather, it addresses symptoms. Treatment plans are developed based on the patient’s age, sex, health status, symptoms, and lifestyle. Changes in the patient’s symptom profile over time require changes or alterations in the treatment regimen. The goals of SLE treatment are to produce symptomatic relief, prevent exacerbations of the disease, treat the exacerbations when they occur, and minimize organ damage and complications. Pharmacologic agents used in SLE treatment regimens include nonsteroidal anti-inflammatory drugs (NSAIDs), antimalarials, corticosteroids, and immune suppressants.
Complications
• Anemia
• Behavioral changes
• Endocarditis
• Kidney damage
• Myocardial infarction
• Myocarditis
• Opportunistic infection(s)
• Osteonecrosis
• Pericarditis
• Pleurisy
• Premature atherosclerotic heart disease
• Renal failure
• Seizures
• Vasculitis
Anesthesia Implications
Preoperative concerns for the patient with SLE center primarily on the renal and pulmonary manifestations of the disease. Secondary concerns center on any cardiac manifestations. Preoperatively, the patient with SLE should have serum creatinine and blood urea nitrogen (BUN) levels determined to ascertain the degree of renal involvement. The anesthetist must take care to avoid drugs heavily dependent on renal excretion if renal insufficiency is highly suspected or demonstrated.
Pulmonary Manifestations
• Bronchiolitis
• Chronic interstitial lung disease
• Diffuse alveolar hemorrhage
• Interstitial pneumonia
• Lupus pleuritis
• Lupus pneumonitis
• Pulmonary embolism
• Pulmonary hypertension
• Respiratory muscle dysfunction
The patient with SLE must also receive a thorough preoperative pulmonary evaluation, including chest x-ray, pulmonary function test (PFT), and arterial blood gas analysis. PFT results often demonstrate a restrictive pattern in patients with SLE. Therefore the anesthetist should increase the inspiratory:expiratory ratio to 1:2.5 or 1:3 to reduce the potential for air trapping. The patient with SLE who demonstrates interstitial disease will likely have decreased diffusing capacity. Loss of diffusing capacity may prolong inhalational agent concentration changes and may prolong both induction and emergence as well. If the patient with SLE also has bronchiolitis, the PFT results may show an obstructive pattern. Postoperative ventilatory support may be necessary for the patient with significant pulmonary dysfunction. The anesthetist must communicate this possibility to the patient preoperatively.
