Condition Deep-Dives 12 min read·Updated 22 July 2026 Clinician-reviewed

Collapsing Glomerulopathy

A UK Consultant Nephrologist on collapsing glomerulopathy — the most aggressive FSGS variant, where APOL1 genotype, viral triggers and drug exposures collide to drive massive proteinuria and rapid CKD.

  • Clinically Reviewed
  • NHS & NICE Aligned
  • UK Evidence-Based
  • Last Reviewed 22 July 2026

Professor Mohammed Mahdi Althaf

Consultant Nephrologist & Acute Physician

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Professor Mohammed Mahdi Althaf

MD, MSc, PgDip (Clin Ed), FRCP, FHEA, FASN

Consultant Nephrologist & Acute Physician · GMC 7216325

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Direct answer

Aggressive FSGS variant. Massive proteinuria, rapid eGFR decline. APOL1 high-risk genotype + viral (HIV, COVID, parvovirus) or drug (pamidronate, interferon) trigger. Treat the cause; primary disease responds variably to high-dose steroids.

Key recommendation: Tuft collapse + podocyte pseudocrescents on biopsy.

Quick answer

✓ Best choices

  • Plant proteins: beans, lentils, tofu, tempeh, chickpeas
  • Vegetables, fruit and whole grains
  • Oily fish 1–2 times a week
  • Olive oil as the main cooking fat

✓ Foods to limit

  • Added salt (≤ 6 g/day)
  • Processed meats and high-additive ready meals
  • Excess animal protein at every meal

Key takeaway

Aggressive FSGS variant. Massive proteinuria, rapid eGFR decline. APOL1 high-risk genotype + viral (HIV, COVID, parvovirus) or drug (pamidronate, interferon) trigger. Treat the cause; primary disease responds variably to high-dose steroids.

Who should be cautious

People on dialysis, post-transplant, pregnant or breastfeeding, or taking prescription medication — confirm with your renal team before changes.

Collapsing Glomerulopathy

Pathology & APOL1

Biopsy

  • Global or segmental glomerular tuft collapse
  • Overlying hyperplastic/hypertrophic podocytes (pseudocrescents)
  • Severe tubular dilatation with microcysts
  • Tubuloreticular inclusions on EM (interferon signature) in HIVAN/lupus/COVAN
  • Often coincident classic FSGS lesions

Apol1

  • Chromosome 22, encodes apolipoprotein L1
  • G1 (S342G/I384M) and G2 (Δ388/389) alleles confer trypanolytic protection but kidney risk
  • Two-allele genotype = 'high-risk' (recessive)
  • 12–15% prevalence in West African ancestry; rare in European/Asian
  • 7–10× risk of FSGS, HIVAN, lupus nephritis ESKD, hypertensive CKD
  • 'Second hit' often required (virus, interferon, drug)

Clinical features & investigations

Presentation

  • Massive proteinuria (often > 10 g/day)
  • Hypoalbuminaemia, oedema, hypertension
  • Rapid eGFR decline (weeks to months)
  • Microscopic haematuria common
  • Constitutional symptoms if viral trigger

Investigations

  • HIV test (urgent — HIVAN curable with ART)
  • SARS-CoV-2 PCR ± antibodies (COVAN)
  • Parvovirus B19, EBV, CMV serology
  • Drug history (pamidronate, interferon, anabolic steroids, lithium)
  • ANA, ENA, complements (SLE)
  • APOL1 genotyping (R225 NHS test directory or research-clinical)
  • Native kidney biopsy with EM essential

Imaging

  • Kidneys typically normal-sized or enlarged early
  • Echogenic on US
  • Document baseline for progression monitoring

Treatment by aetiology

Hivan

  • Antiretroviral therapy first-line (combination including integrase inhibitor)
  • Proteinuria reduces, eGFR stabilises in majority
  • ACE-i / ARB throughout
  • Avoid TDF in significant CKD (use TAF)

Covan

  • Supportive; manage AKI per NICE NG148
  • ACE-i / ARB once stable
  • Steroids variably effective
  • APOL1 high-risk strongly associated

Drug-induced

  • STOP pamidronate / interferon / anabolic steroid
  • Recovery often partial; some progress to ESKD

Primary / Idiopathic

  • High-dose prednisolone 1 mg/kg/day (max 80 mg) × 12–16 weeks → taper
  • Calcineurin inhibitor (ciclosporin or tacrolimus) for steroid-resistant
  • Rituximab in selected refractory cases
  • Plasmapheresis for severe presentations

Lupus-associated

  • Treat per ISN/RPS lupus nephritis class
  • Often class V + collapsing component

SUPPORTIVE (always):

  • ACE-i / ARB (proteinuria target < 1 g/day)
  • SGLT2 inhibitor (dapagliflozin) for proteinuric CKD
  • Statin
  • Anticoagulation if albumin < 25 g/L and very high proteinuria (LMWH or DOAC)
  • Pneumococcal + influenza + COVID vaccination

Transplant

  • Recurrence 30–40% (especially primary FSGS variant)
  • Avoid live donors with two APOL1 risk alleles
  • Pre-emptive plasmapheresis ± rituximab in high-risk cases

UK Pathway

  • Nephrology + virology + (if HIV) infectious diseases
  • National Renal Genetics Service for APOL1 work-up
  • Listed for renal transplant after careful counselling
FSGS — Focal Segmental Glomerulosclerosis
Related reading: FSGS — Focal Segmental Glomerulosclerosis.

Key practical tips

Designed for quick scanning — what to order, what to avoid, sensible portions, common mistakes.

  • Take prescribed ACE inhibitor / ARB / SGLT2 inhibitor consistently — diet works alongside, not instead
  • Monitor BP at home weekly
  • Review urine ACR with your team to track progress

Clinical guidance

TL;DR summary

Aggressive FSGS variant. Massive proteinuria, rapid eGFR decline. APOL1 high-risk genotype + viral (HIV, COVID, parvovirus) or drug (pamidronate, interferon) trigger. Treat the cause; primary disease responds variably to high-dose steroids.

Key takeaways
  • Tuft collapse + podocyte pseudocrescents on biopsy.
  • APOL1 G1/G2 risk alleles drive susceptibility.
  • HIVAN responds to ART; always screen HIV.
  • COVAN: AKI peak in SARS-CoV-2 infection.
  • Pamidronate-induced — STOP the drug immediately.
Kidney Diet & Nutrition Considerations

When protein is leaking into the urine, the goal is to protect the remaining kidney function. Dietary protein should be sensible — neither very high nor unnecessarily low — and a Mediterranean-style plate with reduced salt supports both blood pressure and albuminuria reduction alongside ACE inhibitors, ARBs or SGLT2 inhibitors.

Foods to prioritise

  • Plant proteins: beans, lentils, tofu, tempeh, chickpeas
  • Vegetables, fruit and whole grains
  • Oily fish 1–2 times a week
  • Olive oil as the main cooking fat

Foods to limit

  • Added salt (≤ 6 g/day)
  • Processed meats and high-additive ready meals
  • Excess animal protein at every meal

Potassium, phosphate and protein needs vary between individuals — please confirm personal targets with your renal team or dietitian. Browse the Kidney Diet Hub for more guides in this cluster.

Frequently asked questions

What is collapsing glomerulopathy?

Collapsing glomerulopathy (CG) is an aggressive variant of FSGS characterised on biopsy by global or segmental collapse of the glomerular tuft with overlying podocyte hyperplasia and pseudocrescents. It presents with massive proteinuria (often > 10 g/day), rapid decline in eGFR and frequent progression to ESKD within months without treatment. APOL1 high-risk genotype (two risk alleles, mainly in West African ancestry populations) is the major susceptibility factor in many forms.

What causes it?

Genetic: APOL1 high-risk genotype (G1/G1, G2/G2, G1/G2 — 12–15% prevalence in West African ancestry). Viral: HIV (HIVAN), SARS-CoV-2 (COVAN), parvovirus B19, EBV, CMV. Drugs: pamidronate (high-dose IV bisphosphonate), interferon (α, β, γ), anabolic steroids, lithium. Autoimmune: SLE. Idiopathic / primary collapsing FSGS. Always genotype APOL1 and screen for HIV / HCV / SARS-CoV-2.

How is it treated?

Disease-modifying: HIVAN — antiretroviral therapy (ART) is first-line; reduces proteinuria and stabilises eGFR. COVAN — supportive; some respond to ACE-i ± steroids. Drug-induced — STOP the offending agent (pamidronate, interferon). Primary / idiopathic — high-dose oral prednisolone 1 mg/kg/day (up to 80 mg) for 12–16 weeks then taper, ± calcineurin inhibitors (ciclosporin, tacrolimus), rituximab in selected cases. Always add ACE-i/ARB, SGLT2 inhibitor, statin and nephrotic-syndrome supportive care.

What is the prognosis?

Historically very poor — > 50% reach ESKD within 1–3 years. HIVAN now has substantially better prognosis on ART. COVAN often has rapid AKI but variable longer-term outcome. APOL1-driven disease and primary collapsing FSGS retain the worst prognosis. Recurrence after kidney transplant occurs in 30–40%; APOL1 genotype of donor and recipient is increasingly considered in selection.

Can diet reduce protein in urine?

A reduced-salt, Mediterranean-style diet with sensible protein intake can lower urine protein, particularly when combined with prescribed ACE inhibitors, ARBs or SGLT2 inhibitors. Very low-protein diets are not routinely recommended without dietitian supervision.

Nutritional challenges in kidney disease

Many people living with kidney disease have to limit foods because of potassium, phosphate, diabetes, dialysis, appetite changes or simply the time it takes to cook from scratch every day. That can make it harder to keep daily nutrition balanced — particularly for vitamins and minerals that food alone may not fully cover.

Kidney Vitality is a UK-formulated daily nutritional support product designed by Consultant Nephrologist Professor Mohammed Mahdi Althaf with renal nutrition in mind from the start. It keeps doses moderate, leaves out added potassium, phosphate and magnesium, and avoids megadose vitamin A — sitting alongside a kidney-friendly diet, not replacing it.

Why Kidney Vitality fits this need

Built around UK guidance

Aligned with KDIGO 2024 GN guideline, BHIVA renal disease in HIV guidance and NHS R204 Genomic Test Directory (APOL1).

Designed by a UK Consultant Nephrologist

Formulated and reviewed by Professor Mohammed Mahdi Althaf (GMC 7216325).

Genotype-aware & aetiology-led

Practical APOL1 testing pathway and trigger-specific treatment algorithm covering HIVAN, COVAN, drug-induced and primary disease.

Designed by a UK Consultant Nephrologist

Ready to support your kidney health?

If you have been researching kidney health, supplements, CKD nutrition or kidney-friendly living, Kidney Vitality was developed specifically around those principles by Professor Mohammed Mahdi Althaf (GMC 7216325). Nephrologist Developed Daily Multivitamin.

  • No Added Potassium
  • No Added Magnesium
  • No Added Phosphorus
  • No Added Iron
  • One capsule daily
  • UK GMP — BRCGS, NSF GMP, Halal
Subscribe & Save — £20.39/monthCheck your current multivitamin

✓ Free UK tracked delivery  ·  ✓ Delivered every 30 days  ·  ✓ Pause or cancel anytime  ·  ✓ Never run out

ComparisonKidney VitalityTypical high-street multivitamin
Added potassiumNoneOften included
Added phosphateNoneOften included (E338–E452)
Vitamin A (retinol)No megadoseOften high-dose retinol
Kidney-focused formulationYesNo — general population
Consultant Nephrologist involvementYes (GMC 7216325)No
UK GMP manufacturedYes (BRCGS, NSF GMP)Varies

Food supplement. Not a medicine and not a treatment for kidney disease. Speak with your GP, pharmacist or renal team before starting any new supplement, especially in advanced CKD, on dialysis, post-transplant, pregnant or breastfeeding.

Clinical reviewer

Professor Mohammed Mahdi Althaf

Consultant Nephrologist

Acute Physician

GMC 7216325

View Full Biography

Professor Mohammed Mahdi Althaf is a UK Consultant Nephrologist and Acute Physician with a special interest in chronic kidney disease, AKI prevention and renal nutrition. He combines hospital practice with patient education and clinical guidance review.

View professional profile →
View Credentials
  • MD
  • MSc
  • PgDip (Clin Ed)
  • FRCP
  • FHEA
  • FASN

About this article

Written for UK patients and based on:

  • NICE guidance
  • NHS resources
  • British Dietetic Association guidance
  • Kidney Care UK resources
View methodology

Each article is researched against current UK clinical guidance (NICE NG203, NG118, NG136), NHS patient resources, KDIGO and KDOQI international guidelines, and the British Dietetic Association Renal Nutrition Group. Drafts are written by the Kidney Vitality editorial team and reviewed by a UK Consultant Nephrologist before publication. Content is reviewed on a rolling basis and updated when guidance changes.

Editorial standards

  • Clinically reviewed
  • NHS-aligned
  • NICE-aligned
  • Evidence-based
  • Reviewed before publication
View full editorial process

Every article is researched and written by the Kidney Vitality editorial team using current UK clinical guidance (NICE NG203, NG118, NG136), NHS patient resources, KDIGO/KDOQI international guidelines, and British Dietetic Association renal nutrition guidance. Drafts are reviewed for clinical accuracy by Professor Mohammed Mahdi Althaf, MD, MSc, PgDip (Clin Ed), FRCP, FHEA, FASN (Consultant Nephrologist & Acute Physician, GMC 7216325) before publication. Content is updated when UK guidance changes.

References (4)View Sources
  1. NICE NG203: Chronic kidney disease — assessment and management
  2. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of CKD
  3. KDOQI Clinical Practice Guideline for Nutrition in CKD: 2020 Update
  4. British Dietetic Association — Renal Nutrition Group

Medical disclaimer

This content is educational only and does not replace personalised medical advice.

Read full disclaimer

This page is general information, not personal medical advice. If you have chronic kidney disease, are on dialysis, have had a kidney transplant, are pregnant or breastfeeding, or take prescription medication, please confirm any supplement with your GP, pharmacist or renal team before starting.

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