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Management of Systemic Lupus Erythematosus

           The 2012 American College of Rheumatology (ACR) guidelines state
           that findings for LN are: 18
               persistent proteinuria >0.5 in UPCR or >0.5 g/day in 24hUP or
                urine dipstick ≥3+
               active  urinary  sediment  (defined  as  >5  red  blood  cells  [RBCs]
                per  high  power  field  [hpf];  >5  white  blood  cells  [WBCs]/hpf  in
                the absence of infection or cellular casts limited to RBC or WBC
                casts)

           •   Liver function tests
           The  standard  liver  function  test  (LFT)  includes  measurement  of
           transaminases and serum albumin. Liver involvement in SLE is relatively
           rare and deranged LFTs can be due to a wide variety of aetiologies
           including lupus hepatitis or secondary to co-morbidities e.g. fatty liver
           or viral hepatitis. 19, level II-2  Hypoalbuminemia in SLE is associated with
           disease activity e.g. LN, protein-losing enteropathy and chronic lupus
           peritonitis with ascites. 20, level III
           •   Acute phase reactants
           ESR and CRP levels are the most widely used indicators of the acute
           phase response to inflammation. ESR is often raised in active SLE but
           is not a reliable marker of disease activity as it does not differentiate
           between active lupus and infection. CRP is usually normal or slightly
           elevated in the presence of serositis or arthritis. A significantly raised
           CRP often indicates infection, therefore patients need to be screened
           thoroughly for it. 21

           •   Antinuclear antibodies
           Autoantibodies to intracellular antigens, historically known as ANA, are
           serological  biomarkers  that  have  a  central  role  in  the  diagnosis  and
           classification of systemic autoimmune rheumatic diseases.
           Testing for ANA should be performed only when there is a high clinical
           suspicion of SLE. ANA is present in 95% of SLE patients. Negative
                         22
           test of ANA suggests a low clinical probability of the patients having
           SLE. 21
           ANA  detection  can  be  performed  by  enzyme-linked  immunosorbent
           assay (ELISA), indirect immunofluorescence (IIF) and other techniques.
           The IIF using HEp-2 substrate is the “gold standard” for primary ANA
           detection because of its overall high sensitivity.  ELISA technique is
                                                  22
           less sensitive than IIF, but it has the advantages of being less laborious,
           less subjectivity in its interpretation and can be automated. For these
           reasons, ELISA technique is widely used locally; however IIF may be
           used for confirmation when indicated.




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