Lupus Nephritis and Immune-Complex Disease — Advanced

Renal biopsy is indicated promptly for presentations suggesting active, potentially progressive glomerular disease: nephrotic-range proteinuria with active sediment (A), rapid loss of kidney function with RBC casts (B), new heavy proteinuria with serological evidence of activity (D), and new nephritic syndrome (E) — all warrant biopsy to determine class, activity and chronicity and guide immunosuppression. By contrast (C) an isolated, low-grade, stable proteinuria with inactive sediment and stable renal function in a patient with otherwise quiescent SLE can usually be monitored clinically and biochemically rather than proceeding immediately to biopsy. The decision must always be individualised, but (C) is the least likely scenario to require immediate biopsy. Alternatives: A, B, D and E all represent situations where histological classification will change management and therefore biopsy is appropriate.

ISN/RPS class V (membranous) LN is characterised by predominantly subepithelial immune-complex deposition along the GBM producing a granular immunofluorescence pattern and the so-called ‘spike-and-dome’ appearance on silver stain/electron microscopy. Choice A describes this and is therefore correct. Choice B describes subendothelial deposition and endocapillary proliferation typical of proliferative (class III/IV) LN. Choice C corresponds to isolated mesangial lupus nephritis (class II). Choice D indicates linear IgG along the GBM seen in anti-GBM disease, not immune-complex membranous LN. Choice E is typical of pauci-immune ANCA-associated GN rather than immune-complex LN. Correct interpretation of deposit location and associated light-microscopy changes is essential for classifying LN and directing therapy.

Randomised trials and guideline syntheses indicate that MMF is at least as effective as intravenous cyclophosphamide for induction therapy in proliferative (class III/IV) LN and is widely accepted as a first-line option alongside cyclophosphamide (thus option C is true). Option A is incorrect because cyclophosphamide is not the only effective induction agent; MMF is an established alternative. Option B is incorrect — high‑dose corticosteroids alone are inadequate for most cases of severe proliferative LN. Option D is incorrect — azathioprine is used for maintenance therapy but has inferior induction efficacy compared with MMF/cyclophosphamide. Option E is false as stated here — calcineurin inhibitors are not absolutely contraindicated and can be used in some induction/combination regimens (though use must consider nephrotoxicity); however they are not the universally preferred induction agents for severe proliferative disease. Therefore the best-supported statement is that MMF and cyclophosphamide are evidence-based induction options (C).

A high chronicity index denotes established irreversible structural damage (glomerulosclerosis, interstitial fibrosis, tubular atrophy). Such changes predict a limited likelihood that intensified immunosuppression will recover renal function; management shifts towards supportive care for chronic kidney disease and careful consideration of risks vs benefits of further immunosuppression. Thus option B is correct. Option A is false — high chronicity predicts poor, not excellent, response. Option C is incorrect because chronicity does have prognostic significance and should influence management decisions. Option D is incorrect — further cyclophosphamide is unlikely to reverse chronic scarring and may cause harm. Option E is wrong — chronicity reflects scarring rather than active immune-mediated deposits that would be cleared by plasmapheresis. Biopsy activity versus chronicity indices guide expectations and therapy selection.

Azathioprine is considered acceptable for use in pregnancy when immunosuppression is required for SLE or lupus nephritis; it has a well-documented safety profile in pregnancy at usual doses (option D correct). MMF (A) is teratogenic and should be stopped preconception. Cyclophosphamide (B) is strongly teratogenic, particularly in the first trimester, and associated with gonadotoxicity; it may be used in life‑threatening situations with specialist input but is not regarded as acceptable routine maintenance in pregnancy. Methotrexate (C) and leflunomide (E) are teratogenic and contraindicated. When immunosuppression is needed in pregnancy, azathioprine and some calcineurin inhibitors are considered among the safer options in specialist guidance; drug changes should ideally be made prior to conception.

APS nephropathy is characterised by thrombotic lesions in small renal arteries, arterioles and capillaries leading to chronic ischaemic damage. Long-term anticoagulation (typically warfarin for thrombotic APS) is central in preventing recurrent thrombotic events and progression (B correct). High-dose immunosuppression (A) is not the primary long-term therapy unless there are superimposed immune-mediated lesions. Plasmapheresis (C) is not used routinely as long-term therapy for APS nephropathy. Statement D is false; APS nephropathy can cause progressive CKD. Statement E is incorrect — antiplatelet therapy alone is insufficient for most patients with thrombotic APS who generally require anticoagulation. Management must be individualised and coordinated with rheumatology/haematology specialists.

Serial measurements of complement (C3/C4) and anti-dsDNA have greater clinical utility than isolated values because trends (falling complements, rising anti-dsDNA) often precede or accompany disease flares, including renal flares (A correct). A single normal complement and anti-dsDNA (B) does not reliably exclude active LN — false negatives occur. Statement C is incorrect — anti-dsDNA can correlate with disease activity, albeit imperfectly. Statement D is wrong — complements characteristically fall (not rise) in active disease. Statement E is incorrect — urine sediment and quantitative proteinuria are essential in assessment; serology alone is insufficient to decide biopsy. Clinical context and trends guide decisions about investigation and biopsy.

The correct option is B: guideline recommendations and expert consensus commonly recommend co-trimoxazole prophylaxis against Pneumocystis jirovecii pneumonia for patients receiving intensive immunosuppression (high‑dose steroids, cyclophosphamide, MMF or combined therapy). Choice A (valacyclovir) is not routinely used for CMV prophylaxis in this setting unless there is a specific risk or prior CMV disease. Choice C (routine IVIG) is not standard for prophylaxis against infection in LN induction. Choice D (routine fluconazole) is not routinely recommended and may cause interactions; antifungal prophylaxis is reserved for specific circumstances. Choice E is false — immunosuppressive induction confers a significant infectious risk and selected prophylactic measures (notably PCP prophylaxis) are standard. (Note: local policies and individual risk assessments guide prophylaxis decisions.)

Recurrent lupus nephritis in the allograft does occur but is uncommon and rarely the dominant cause of graft loss; graft survival is generally determined more by immunological rejection, infection and other complications (B correct). Statement A is incorrect — recurrence is not very common nor the leading cause of graft loss. Statement C is false — active SLE at the time of transplantation may affect timing and peri-transplant management and should not be ignored. Statement D is incorrect — standard transplant immunosuppression is not routinely stopped to prevent recurrence; suppression is required to prevent rejection and may also control SLE. Statement E is wrong — prior lupus nephritis is not an absolute contraindication to transplantation; many patients receive successful transplants. Pre‑transplant disease quiescence and individual assessment are important.

In life‑threatening pulmonary–renal syndrome from severe lupus nephritis (diffuse alveolar haemorrhage with rapidly progressive GN), immediate aggressive therapy is required. The recommended urgent approach is high‑dose intravenous corticosteroids and cytotoxic therapy such as cyclophosphamide; plasmapheresis is considered when alveolar haemorrhage is severe or when anti‑GBM or other antibody-mediated disease is suspected/possible. Thus option B is the appropriate immediate strategy (correct). Option A (oral prednisone alone) is inadequate for life‑threatening disease. Option C is incorrect — immunosuppression is often lifesaving in pulmonary haemorrhage due to SLE. Option D is incorrect — while rituximab can be used, it is not established as the sole immediate first-line monotherapy in this acute setting; cyclophosphamide plus steroids is the standard initial combination in many guidelines, with rituximab considered in refractory cases or particular circumstances. Option E is wrong — renal replacement therapy may be required for kidney failure but does not treat the underlying immunological process causing haemorrhage. Management should be urgent, multidisciplinary (renal, respiratory, rheumatology, ICU) and individualised.