Systemic lupus erythematosus: Difference between revisions

Systemic lupus erythematosus (<abbr>SLE</abbr>) is the prototype of multisystemic autoimmune diseases, affecting all organ systems. Its severity can range from mild to severe and life-threatening.

* High oestrogenic state (oral contraceptives, endometriosis)

* Smoking

Drug-induced lupus erythematosus is an SLE-like syndrome caused by certain drugs. The most commonly identified drugs are procainamide, hydralazine, and <abbr>TNF</abbr>-α inhibitors. The first two have the highest risk but aren’t widely used anymore.

The most common musculoskeletal symptom is non-erosive symmetrical polyarthritis affecting distal joints.

The renal manifestation of lupus is called lupus nephritis, which is covered in detail in nephrology. It’s a severe complication and a major cause of death in SLE. 50% of SLE patients develop lupus nephritis at some point, but only 20% have it at the time of diagnosis. The presence of lupus nephritis in a patient with SLE means a worse prognosis and usually alterations in treatment. There are six different classes (types) of lupus nephritis with very variable prognosis. Class I (minimal mesangial type) has the best prognosis, while class IV (diffuse proliferative) has the worst. Clinically, lupus nephritis may present as isolated proteinuria or haematuria, or any nephrological syndrome.

CNS manifestations may be anything from headaches to psychosis and seizures. Cardiovascular manifestations may be myocarditis, valvular disease, and accelerated atherosclerosis. Pulmonary manifestations include interstitial lung disease, pneumonitis, and pulmonary hypertension. Any serous membrane may be inflamed.

Any haematological cell line may be affected, causing anaemia, leukopaenia, lymphocytopaenia, or thrombocytopaenia. <abbr>GI</abbr> manifestations include abdominal pain, peritonitis, ascites, pancreatitis, and hepatitis.

SLE is a clinical diagnosis based the presence of certain diagnostic criteria. Previously, the ACR or SLICC criteria were used. However, in 2019, a comprehensive and more sensitive and specific set of criteria was released, the ACR/EULAR criteria. These criteria give points based on typical clinical features, laboratory findings, serology, and renal biopsy findings. The “entry criterion” is an ANA titre of > 1:80, meaning that this is an obligatory finding for the diagnosis (98% sensitive).

* Autoimmune haemolysis

* Elevated ESR (normal <abbr>CRP</abbr>)

* ANA titre > 1:80

* Presence of antiphospholipid antibodies

** Anti-dsDNA

** Anti-Sm

Important lifestyle changes include appropriate sun protection, smoke cessation, exercise, and adherence to vaccination protocols. NSAIDs can provide symptomatic relief.

Pharmacological treatment can be considered in three different forms: induction of remission, maintenance of remission, and supportive treatment. Side effects of pharmacological therapy is unfortunately a major cause of SLE-related morbidity and mortality, mostly due to glucocorticoids.

For induction of remission, glucocorticoids are used. In cases of renal or CNS affection, other immunosuppressants like cyclophosphamide or mycophenolate mofetil may also be necessary.

For maintenance of remission, hydroxychloroquine is indicated in all patients as it effectively reduces morbidity and mortality. Other immunosuppressants, like azathioprine, methotrexate, and sometimes even long-term low-dose glucocorticoids, may be required. Belimumab and rituximab are the only biological therapies indicated for SLE.

Supportive treatment includes medications like ACE inhibitors, ARBs, statins, antiepileptics, bisphosphonates, etc.