Classic global granular capillary wall staining with IgG in this case of membranous nephropathy. #renalpath #pathsky #nephsky

Young F pt with nephrotic range proteinuria. Membranous pattern injury with near negative frozen IF. Pronase IF unmasks IgG-K staining. SAP is positive. Membranous-like glomerulopathy with masked IgG-kappa deposits. pubmed.ncbi.nlm.nih.gov/32001064/ #renalpath #nephsky #pathsky

Case of IgAN with massive hemispherical mesangial deposits. Mimics cryo-plugs but deposits are mesangial rather than filling capillary loops. #renalpath #pathsky #nephsky

Pauci-Immune Endocapillary Proliferative GN with Glomerular M2 Macrophage Infiltration - Kidney International Reports www.kireports.org/article/S246...

Dual AL/AH amyloidosis in a pt with plasma cell dyscrasia. Mass spec was confirmatory. #renalpath #pathsky #nephsky

Another example of how IgAN is not a benign disease. Middle age pt with CKD, hematuria, proteinuria. Strong mesangial IgA staining and deposits by EM. Unfortunately extensive IFTA at diagnosis. Can we catch these pts earlier? #renalpath #athsky #nephsky

Well formed non-necrotizing granulomas in a pt with worsening renal function and sarcoidosis. Some granulomas in peri-vascular locations without vasculitis. #renalpath #pathsky #nephsky

Some smudgy mesangial IgG staining indicating a surprise fibrillary GN superimposed on advanced diabetic nephropathy. EM was confirmatory (~14 nm fibrils in some mesangial areas) as was the DNAJB9 stain. Value of biopsy in diabetic pts. #renalpath #nephsky #pathsky

Bx for progressive CKD in a pt with CML, in remission. Limited biopsy with prominent debris filled proximal tubule lysosomes + for lysozyme (no evidence for light chain restriction (F/P) or chromogranin). Suspicious for lysozyme nephropathy. #renalpath #pathksy #nephsky

One of the more subtle cases of amyloidosis I have seen. Few spicules on silver stain. Minimal congo red positivity. Despite early amyloid deposition, pt had nephrotic syndrome. Likely AL type (pt has LPL); MS pending. #renalpath #pathsky #nephsky

So many eosinophils in this case of tubulointerstitial nephritis secondary to recent antibiotic administration. Few tiny granulomas as well. Eos seen in EM as well. #renalpath #pathsky #nephsky

Unfortunate but not rare IgAN presentation. Pt in their 30's, no PMHx, presented with HTN emergency, CKD, hematuria, proteinuria. Advanced IgAN with severe IFTA, focal active crescents (M1 E1 S1 T2 C1). Wish we could catch these cases earlier. #renalpath #pathsky #nephsky

Unusual granular casts with annular appearance. Light chain, hemoglobin, myoglobin, chromogranin casts excluded. Patient on IV vancomycin. Suspicious for vancomycin cast nephropathy. pubmed.ncbi.nlm.nih.gov/31871855/ #renalpath #pathsky #nephsky

Renal hemosiderosis secondary to intravascular hemolytic anemia doi.org/10.1016/j.kint.2025.05.033 🔹Rare case of secondary renal hemosiderosis after valve surgery 🔹Beautiful histology, Prussian blue, and EM images showing hemosiderin deposit #MedSky #NephSky @umontreal-en.bsky.social

Diagnosis unmasked. Young F with 2g proteinuria, weak +dsDNA. Membranous pattern, IF with C3 dominant staining. Pronase IF --> IgG-k. Membranous-like glomerulopathy with masked monotypic IgG-k deposits. Considered to be autoimmune; not MGRS. #renalpath #pathsky #nephsky.

BK nephropathy Clues: - Heavy but focal tubulointerstitial inflammation - Increased plasma cells - Viral cytopathic change - Features of CNI toxicity ->over immunosuppression (isometric vacuolization shown here) -SV40 IHC confirmatory #renalpath #pathsky #nephsky

Arteriole with features of a old recanalized thombus in a transplant kidney biopsy. Multiple slit like vascular spaces within the fibrotic lumen. Not a lesion I see often. Pt had clinically diagnosed TMA a few months prior. #renalpath #pathsky #nephsky

Chronic active ABMR in patient with worsening proteinuria, renal function, positive DSA *Glomerulitis (shown in image) *Transplant glomerulopathy (shown in image) *Peritubular capillaritis *Diffuse C4d+ in PTCs on IF #renalpath #transplant #pathsky #nephsky #medsky

NELL-1 IHC can also be tricky to interpret as there is significant podocyte cytoplasmic staining in the negative control. Must show granular capillary wall deposits which match deposits by IF and EM. #renalpath #pathsky #nephsky

Illustrative example of a segmental membranous nephropathy pattern (segmental granular IgG staining) which is often seen with NELL-1+ (IHC) MN as in this case. Deposits present in only some loops by EM. #renalpath #pathsky #nephsky

Intimate contact between endothelial cell and mesangial cell cytoplasm. A reminder that no GBM separates the blood space from the mesangium. I wonder what secrets they are sharing. #renalpath #pathsky #nephsky

Severe vascular rejection hiding in the IF tissue. Fibrinoid necrosis really pops on the H&E and further confirmed by fibrinogen IF. #renalpath #pathsky #nephsky

Laser microdissection followed by mass spectrometry (LMD/MS) shows promise as a more sensitive approach to tissue diagnosis of PLA2R-associated membranous nephropathy. Read more in #ASNKidneyNews kidney.pub/KN1710-09#ASNKidneyNews

📽️✨An inside look at life in the UCLA Pathology Residency Program! We’re excited to share the moments that shape our residents - from the microscope to mentorship, and everything in between. Watch the full video ➨ youtu.be/Yfw39_U9_Hg #pathology #PathSky #PathMatch26 #PathMatch #Match2026

Teenager with nephrotic syndrome. Biopsy revealed unusual case of membranous nephropathy in a peds patient. PLA2R positive (IHC). PLA2R most common antigen in peds MN. EXT1/2 also common, SEMA3B less common. (pubmed.ncbi.nlm.nih.gov/38025223/) #renalpath #pathsky #nephsky

A startling biopsy. Severe acute TMA in a pt with suspected scleroderma renal crisis. Massive vascular thrombosis, mucoid intimal edema, and early onion skin change associated with severe cortical necrosis. #renalpath #nephsky #pathsky

Bx for nephrotic syndrome in an IV drug user with multiple infections. LM was all medulla, but good enough to make a diagnosis. AA amyloidosis; very common bx result in this clinical setting. #renalpath #pathsky #nephsky

Bx for new onset NS in an older adult. Serologic work up including SPEP/UPEP IFE negative. Bx shows membranous pattern with few double contours. IgG3-k restriction and mottle EM deposits c/w PGNMID with membranous predominant pattern. PLA2R- #renalpath #pathsky #nephsky

Kidney txp biopsy for AKI (~6 post txp). Tubular injury associated with granular and ropey trichome positive casts. IHC confirmed myoglobin cast nephropathy. CK found to be very high; thought to be due to statin related myopathy. #renalpath #pathsky #nephsky

Heavy Chains, Heavy Consequences: A Case of Concomitant Heavy Chain Amyloidosis and Heavy Chain Deposition Disease. Fibrils and powdery deposits. #renalpath #nephsky #pathsky www.sciencedirect.com/science/arti...

🔬 We are now recruiting a Renal Pathologist! #pathology #path2path #PathSky #renalpath Join our team today! ➨ bit.ly/46CqsrU

Multiple diagnoses not uncommon in kidney biopsies. This case showed nodular diabetic nephropathy, a mostly chronic ANCA associated GN, and to top it off some interstitial ALECT2 amyloidosis. #renalpath #nephsky #pathsky

Lupus nephritis case with prominent podocyte cytoplasmic vacuolization on LM with myelin figures revealed by EM. Probably HCQ effect but given its prominence genetic etiologies should be excluded (e.g., Fabry, LMX1B). #renalpath #pathsky #nephsky

Interesting case of AL-amyloidosis. Massive vascular deposits, even in hilar arterioles with glomerular sparring. Patient had minimal proteinuria given lack of glomerular amyloid. #renalpath #pathsky #nephsky

Nice example of urate crystals in gouty tophi involving the medulla. Polarizable crystals can be see using unstained sections from the IF tissue. #renalpath #pathsky #nephsky

Another example of an 'incidental' finding next to the tumor in a nephrectomy specimen. Amyloidosis (probably LECT2). Reminder not too overlook the non-neoplastic tissue. #renalpath #pathsky #nephsky

ANCA GN Working Group Meeting More info for EUVAS Florence Working Group - Symposium on ANCA GN Classification-Scoring Systems, click link 👉https://vasculitis.org/ Register: app.donorfy.com/form/ZU81NH9... @brixsilke.bsky.social & Ingeborg Bajema #renalpath #vasculitis #pathsky #nephsky

Multi-focal severe necrotizing arteritis in a kidney biopsy with an ANCA vasculitis. Interestingly, foci of arteritis were only present in IF/EM tissue. Illustrating how even when severe arteritis can be easily missed due to sampling in a small biopsy. #renalpath #nephsky #pathsky

Great work by our chief resident @clilleymd.bsky.social on charactering microscopic tubulo-venous communications in kidney biopsies. www.kidneymedicinejournal.org/article/S259... . Here's another nice example (x.com/JZRenalPath/...) #renalpath #pathsky #nephsky

Kidney txp biopsy with histologic features of acute pyelonephritis. Neutrophilic tubulitis, neutrophilic casts, and tubules which seem to explode out. Cellular rejection typically is not neutrophilic and inflammation hits the tubules from the outside in. #renalpath #nephsky #pathsky

The August issue of CJASN is now available online! Topics covered this month include: - GLP-1 receptor antagonists in patients receiving dialysis - Transportation access and dialysis outcomes - and more Check out the issue here: journals.lww.com/cja... #ASNCJASN Cover by @JZRenalpath et al.

🔬 We are now recruiting a Renal Pathologist! #pathology #path2path #PathSky #renalpath Join our team today! ➨ bit.ly/4ll8K09

Wide variety of morphologies in this case of crystalline light chain proximal tubulopathy: mottle lysosomes, crystals, and fibrils. #renalpath #nephsky #pathsky

One of the more subtle amyloid cases I have seen. Just a few deposits in 2 gloms by LM. Just enough congo red staining. Glad to catch it in the EM as well. #renalpath #nephsky #pathsky

Some well formed "eye lashes" on these capillary loops in a case of AL-amyloidosis. Podocytes getting skewered by the spicules in the EM. #renalpath #pathsky #nephsky.

Classic example of Alport spectrum disease in a patient with X-linked Alport syndrome. Lesions of segmental glomerulosclerosis, numerous interstitial foam cells, and atypical GBMs with lamina densa splitting, subepithelial scalloping, and thinning. #renalpath #pathsky #nephsky

Some nice examples of severe tubulitis in this case of ACR 1B. Interestingly bx for new de novo DSA with with stable allograft function (~1 year post txp). No significant MVI. #renalpath #nephksy #pathsky

Alport syndrome (AS) is a hereditary glomerular disease in children characterized by hematuria, proteinuria, & progressive kidney failure. Read these Clinical Insights into a child w/autosomal dominant AS complicated w/steroid-sensitive nephrotic syndrome. link.springer.com/article/10.1...

Check out our latest “What’s New in Pathology” newsletter! June 2025 Issue: "What’s New in Medical Renal Pathology 2025: Updates on Podocytopathy and Immunofluorescence Staining in Medical Kidney" -- Read or download PDF: buff.ly/thzp6rW #Pathology #PathologyOutlines #RenalPath #PathSky

Case of IgAN in the setting cirrhosis with prominent red blood cell casts with fairly focal crescents. Pt was biopsied for gross hematuria. #renalpath #pathsky #nephsky