Case Presentation: A 27-year-old African American female with recent diagnosis of SLE and pending initiation of treatment presented to the outpatient clinic with nausea and vomiting. She was sent to the ED after failing symptomatic treatment for 7 days. In the ED she was found to have fever, tachycardia, periorbital swelling, and tender right submandibular lymphadenopathy. Laboratory data was significant for acute kidney injury with creatinine of 1.4 (baseline creatinine: 1.0 five days prior to admission). The patient was given broad spectrum antibiotics, IV fluids and admitted for further care. Despite negative septic workup and fluid resuscitation, the patient remained febrile and with worsening renal function with creatinine rising up to 4.3. Concern for lupus nephritis as a cause of her symptoms led the team to obtain a kidney biopsy and to the initiation of pulse dose steroids. Further work up for glomerular disease revealed positive ANA, DS DNA, low complement levels and normal c-ANCA and p-ANCA levels. Urine protein/creatinine ratio was 2.2. The kidney biopsy showed collapsing focal segmental glomerulosclerosis (cFSGS) consistent with lupus podocytopathy and lupus nephritis class II. Patient was started on mycophenolate mofetil (MMF). HIV, EBV and hepatitis panel were negative. Kidney function improved to near baseline with initiation of steroids and MMF.
Discussion: Collapsing Glomerulopathy has usually been associated with infectious etiologies including HIV, as well as EBV, and CMV infection. However, this patient presented with acute SLE flare and was found to have collapsing FSGS with concurrent lupus nephritis. Recent reports have shown a genetic link between the APOL1 gene mutation and cFSGS in association with diseases like lupus nephritis. There have been theories that humoral/cell mediated immunity play a key role in the pathogenesis of lupus podocytopathies. It is due to the involvement of the immune pathways that we see partial or complete response to steroids and immunosuppressant’s such as MMF without progressing to ESRD. In our patient, there was a good response to steroids and MMF and renal function improved without dialysis. Gene testing is pending for our patient
Conclusions: Although HIV is known to be the most common culprit of collapsing focal segmental glomerulosclerosis, there has been increasing reports of additional causes of cFSGS. These include secondary systemic lupus erythematous in association with apolipoprotein L1 (APOL1) gene disorder, as well as ischemic insults to the renal parenchyma and additional viral infectious etiologies and drugs. Patients with Collapsing glomerulopathy and Lupus nephritis usually presents with severe renal failure, massive proteinuria and tend to have poor response to steroids and immunosuppressive therapy. Fortunately, our patient responded well to steroids and mycophenolate Mofetil and kidney function improved. However, further documentation and research is required in order to properly understand the disease process and treatment for Collapsing glomerulopathy in SLE patients that are positive for APOL1 gene.