The Risks of Thin Basement Membrane Nephropathy
Section snippets
Nonmedical risks
The most common hazard for the individual with TBMN is the anxiety related to misconceptions about this diagnosis and the inconvenience, expense, and wastefulness of unnecessary investigations. On the other hand, when TBMN is suspected clinically but is not confirmed by renal biopsy examination the diagnostic uncertainty also may result in worry for the individual. Now that the nature of TBMN and its prognosis are better understood it is uncommon (and usually unjustified) for affected
Genetic implications
There are, however, genetic implications in making the diagnosis of TBMN. TBMN is an autosomal-dominantly inherited condition,5, 6, 7 and about two thirds of cases have another family member with hematuria.7 On average, the causative mutation occurs in half of the offspring of an affected parent and equally often in males and females. Females seem to come to medical attention more often than males, possibly because their normally thinner glomerular basement membrane (GBM) is attenuated further
Hematuria
The hematuria in TBMN usually is microscopic, persistent, and dysmorphic, reflecting its glomerular origin.10 Sometimes the hematuria is intermittent, which can interfere with the identification of affected family members. Occasionally, the hematuria is macroscopic and there are rare reports of TBMN associated with loin-pain hematuria syndrome, of urinary red cells blocking the renal tubules and causing acute tubular necrosis, and even of iron deficiency.11, 12, 13
Hypertension, proteinuria, and renal impairment
The most serious complications
Misdiagnosis
The diagnosis of TBMN usually is made clinically (Table 1). TBMN must be distinguished from X-linked Alport syndrome in boys and female carriers (the disease usually is obvious in adult men) and IgA disease because of the very different prognoses for these conditions and because of the possibility of treatment for IgA disease. X-linked Alport syndrome is relatively uncommon but the clinical and ultrastructural features in boys and female carriers closely resemble those seen in TBMN.25 IgA
Pregnancy
Although TBMN is the commonest glomerular lesion worldwide, the effect of pregnancy is not well studied. There are only a few reports of pregnancy in patients with non-IgA mesangial proliferative glomerulonephritis, most of whom have had TBMN.35, 36 In our experience, the outcome for most individuals with TBMN (and their babies) is better than in these series.
Transplantation
Many nephrologists currently use kidneys from donors with TBMN, and this practice appears to have no obvious adverse outcomes for the donors or recipients, at least in the short term.37 However, the real risks of donation and the outcome for allograft recipients are unknown, and, in particular, it is not clear whether they are more prone to the development of glomerulosclerosis, proteinuria, hypertension, or renal impairment in the long term.
References (37)
- et al.
Thin basement membrane nephropathy (TBMN)
Kidney Int
(2003) - et al.
Signs and symptoms of thin basement membrane nephropathyA prospective regional study on primary glomerular disease—The Limburg Renal Registry
Kidney Int
(2004) - et al.
Thin GBM nephropathyPremature glomerular obsolescence is associated with hypertension and late onset renal failure
Kidney Int
(1997) - et al.
Familial and nonfamilial benign hematuria
J Pediatr
(1966) - et al.
Segregation of hematuria in thin basement membrane disease with haplotypes at the loci for Alport syndrome
Kidney Int
(2001) - et al.
COL4A4 mutation in thin basement membrane disease previously described in Alport syndrome
Kidney Int
(2001) - et al.
Red cell traverse through thin glomerular basement membranes
Kidney Int
(2001) - et al.
Loin pain-hematuria syndrome associated with thin glomerular basement membrane disease and hemorrhage into renal tubules
Kidney Int
(1996) - et al.
Thin basement membrane disease and acute renal failure secondary to hematuria and tubular necrosis
Am J Kidney Dis
(2000) - et al.
Genetic polymorphism of NPHS1 modifies the clinical manifestations of IgA nephropathy
Lab Invest
(2003)
NPHS2 R229Q functional variant is associated with microalbuminuria in the general population
Kidney Int
The association of IgA glomerulonephritis and thin basement membrane disease in a hematuric patientLight and electron microscopic and immunofluorescence investigation
Am J Kidney Dis
A comparison of the clinical, histopathologic, and ultrastructural phenotypes in carriers of X-linked and autosomal recessive Alport’s syndrome
Am J Kidney Dis
COL4A3 mutations and their clinical consequences in thin basement membrane nephropathy (TBMN)
Kidney Int
Alport syndrome and thin basement membrane nephropathyUnravelling the tangled strands of type IV collagen
Kidney Int
Abnormally thin glomerular basement membranes associated with hematuria, proteinuria or renal failure in adults
Am J Nephrol
Establishing the diagnosis of benign familial hematuria. The importance of examining the urine sediment of family members
JAMA
Benign familial hematuria due to mutation of the type IV collagen α4 gene
J Clin Invest
Cited by (13)
Thin Glomerular Basement Membrane in a Kidney Transplant of an Alport's Syndrome Patient: A Case Report
2017, Transplantation ProceedingsCorrelates of hematuria on glomerular histology and electron microscopy in IgA nephropathy
2016, Medical Journal Armed Forces IndiaCitation Excerpt :However, in our study, we could not make any such inference. Hematuria is the most17 common clinical presentation of IgA nephropathy, and correlates well with the presence of severe lesions like endocapillary proliferation on biopsy; however, it failed to show a significant correlation with early mild lesion like mesangial expansion and chronic lesion like segmental sclerosis on MEST scoring. A wide range of ultrastructural changes are seen in IgA nephropathy.
Evaluation of the kidney transplant recipient and living kidney donor
2008, Therapy in Nephrology and Hypertension: A Companion to Brenner & Rector's The Kidney, Expert Consult - Online and PrintEvaluation of the Kidney Transplant Recipient and Living Kidney Donor
2008, Therapy in Nephrology & HypertensionResponse to 'Evaluating living kidney donor candidates with minor medical abnormalities' [2]
2007, Kidney InternationalThin basement membrane nephropathy and renal transplantation
2005, Seminars in Nephrology
Supported by the National Health and Medical Research Council of Australia.