Outcome of Renal Transplant in Hereditary Gelsolin Amyloidosis

Membranous nephropathy concurrent with renal amyloidosis: a six-patient report and literature review

The KDIGO 2021 guidelines suggest that individuals who test positive for serum anti-phospholipase A2 receptor (anti-PLA2R) antibodies may not require a renal biopsy to establish a diagnosis of membranous nephropathy (MN). However, it is imperative to acknowledge that MN can coexist with other chronic kidney diseases. In instances where MN is comorbid with IgA nephropathy, diabetic nephropathy, or focal segmental glomerulosclerosis, the therapeutic approach tends to be analogous. Nevertheless, there is a significant disparity in both the treatment regimen and the prognosis between MN and renal amyloidosis, with variations existing even among distinct subtypes of renal amyloidosis. Given that both MN and renal amyloidosis exhibit a predilection for the geriatric population, it is prudent to consider the possibility of MN concurrent with renal amyloidosis in elderly patients who test positive for serum anti-PLA2R antibodies. This consideration should precede a straightforward MN treatment strategy. In this report, we present six patients with MN concurrent with renal amyloidosis identified at our center over the past 14 years; in five of whom were positive for serum anti-PLA2R antibodies. We further elucidated the divergent clinicopathological characteristics and prognostic implications of these cases.

Systemic Amyloidosis and Kidney Transplantation: An Update

Amyloidosis is a heterogeneous disorder characterized by abnormal protein aggregate deposition that often leads to kidney involvement and end-stage kidney disease. With advancements in diagnostic techniques and treatment options, the prevalence of patients with amyloidosis requiring chronic dialysis has increased. Kidney transplantation is a promising avenue for extending survival and enhancing quality of life in these patients. However, the complex and heterogeneous nature of amyloidosis presents challenges in determining optimal referral timing for transplantation and managing post-transplantation course. This review focuses on recent developments and outcomes of kidney transplantation for amyloidosis-related end-stage kidney disease. This review also aims to guide clinical decision-making and improve management of patients with amyloidosis-associated kidney disease, offering insights into optimizing patient selection and post-transplant care for favorable outcomes.

Hearing problems in patients with hereditary gelsolin amyloidosis

BACKGROUND

Gelsolin amyloidosis (AGel amyloidosis) is a hereditary form of systemic amyloidosis featuring ophthalmological, neurological and cutaneous symptoms. Previous studies based mainly on patients' self-reporting have indicated that hearing impairment might also be related to the disease, considering the progressive cranial neuropathy characteristic for AGel amyloidosis. In order to deepen the knowledge of possible AGel amyloidosis-related hearing problems, a clinical study consisting of the Speech, Spatial and Qualities of Hearing Scale (SSQ) questionnaire, clinical examination, automated pure-tone audiometry and a speech-in-noise test was designed.

RESULTS

Of the total 46 patients included in the study, eighteen (39%) had self-reported hearing loss. The mean scores in the SSQ were 8.2, 8.3 and 8.6 for the Speech, Spatial and Qualities subscales, respectively. In audiometry, the mean pure tone average (PTA) was 17.1 (SD 12.2) and 17.1 (SD 12.3) dB HL for the right and left ears, respectively, with no difference to gender- and age-matched, otologically normal reference values. The average speech reception threshold in noise (SRT) was - 8.2 (SD 1.5) and - 8.0 (SD 1.7) dB SNR for the right and left ears, respectively, which did not differ from a control group with a comparable range in PTA thresholds.

CONCLUSION

Although a significant proportion of AGel amyloidosis patients experience subjective difficulties in hearing there seems to be no peripheral or central hearing impairment at least in patients up to the age of 60 years.

Clinical, biopsy, and mass spectrometry findings of renal gelsolin amyloidosis

Gelsolin amyloidosis is a rare type of amyloidosis typically involving the cranial and peripheral nerves, but rarely the kidney. Here we report the clinical, kidney biopsy, and mass spectrometry findings in 12 cases of renal gelsolin amyloidosis. Of the 12 patients, five were men and seven were women with mean age at diagnosis of 63.8 years. Gelsolin amyloidosis was most common in Caucasians (six patients) and Asians (four patients), and included one each African-American and Hispanic patients. Nephrotic syndrome was the most common cause of biopsy, although most patients also had progressive loss of kidney function. Hematological and serological evaluation was negative in 11 patients, while one patient had a monoclonal gammopathy. The renal biopsy showed large amounts of pale eosinophilic Congo red-positive amyloid deposits typically restricted to the glomeruli. Immunofluorescence studies were negative for immunoglobulins in nine cases with three cases of smudgy glomerular staining for IgG. Electron microscopy showed mostly random arrangement of amyloid fibrils with focally parallel bundles/sheets of amyloid fibrils present. Laser microdissection of the amyloid deposits followed by mass spectrometry showed large spectra numbers for gelsolin, serum amyloid P component, and apolipoproteins E and AIV. Furthermore, the p. Asn211Lys gelsolin mutation on mass spectrometry studies was detected in three patients by mass spectrometry, which appears to represent a renal-limited form of gelsolin amyloidosis. Thus, renal gelsolin amyloidosis is seen in older patients, presents with nephrotic syndrome and progressive chronic kidney disease, and histologically exhibits glomerular involvement. The diagnosis can be confirmed by mass spectrometry studies.

Hereditary renal amyloidosis caused by a heterozygous G654A gelsolin mutation: a report of two cases

Finnish-type familial amyloidosis (FAF) is a rare hereditary systemic amyloidosis that mainly exhibits cranial neuropathy. We describe a Japanese family with FAF manifested predominantly as renal amyloidosis. The proband was a 42-year-old woman with a 21-year history of proteinuria due to renal amyloidosis. Her mother was subsequently diagnosed with a similar disorder. After the first renal biopsy, both patients were followed up routinely for a period of 14 years. Genetic analysis of DNA samples revealed a heterozygous G654A gelsolin mutation. Severe renal involvement has not been reported previously in patients with FAF bearing a heterozygous gelsolin mutation.

Global scientific vision with local vigilance: renal transplantation in developing countries

CONTEXT

Renal Transplantation is the most effective treatment for patients with end-stage renal disease, which is fortunately available in the developing countries, even for poor people. Nonetheless, the way forward should be the implementation of advanced science of transplantation, allograft monitoring abilities, knowledge about the epidemiology of renal disease in any specific region, awareness about the influence of ethenic and genetic factors immunosuppressant bioavailability, and post-transplant complications all strongly affecting the patients and allograft survival.

EVIDENCE ACQUISITIONS

In this process we searched mainly in PubMed, Web of Science and Google Scholar data bases for key words of renal allograft monitoring, post-transplant infections, renal/kidney transplantation and Iran. We followed the cross articles to follow our main idea to find a connection between modern advancement in renal allograft monitoring and our practice in developing countries. Another focus was on the special infectious and non-infection complication that do exist in specific region and need specific considerations.

RESULTS

Implementation of modern techniques of immune monitoring, allograft function, awareness about the specific infectious and non-infectious disease in each region improves the quality of renal transplantation.

CONCLUSIONS

We need to combine the advance scientific vision with local vigilance to achieve the best outcome in renal allograft recipients.

Active Achilles tendon kinesitherapy accelerates Achilles tendon repair by promoting neurite regeneration

Active Achilles tendon kinesitherapy facilitates the functional recovery of a ruptured Achilles tendon. However, protein expression during the healing process remains a controversial issue. New Zealand rabbits, aged 14 weeks, underwent tenotomy followed immediately by Achilles tendon microsurgery to repair the Achilles tendon rupture. The tendon was then immobilized or subjected to postoperative early motion treatment (kinesitherapy). Mass spectrography results showed that after 14 days of motion treatment, 18 protein spots were differentially expressed, among which, 12 were up-regulated, consisting of gelsolin isoform b and neurite growth-related protein collapsing response mediator protein 2. Western blot analysis showed that gelsolin isoform b was up-regulated at days 7–21 of motion treatment. These findings suggest that active Achilles tendon kinesitherapy promotes the neurite regeneration of a ruptured Achilles tendon and gelsolin isoform b can be used as a biomarker for Achilles tendon healing after kinesitherapy.

Amyloid nephropathy

Amyloidosis is an uncommon disease that is characterized by abnormal extracellular deposition of misfolded protein fibrils leading to organ dysfunction. The deposited proteins display common chemical and histologic properties but can vary dramatically in their origin. Kidney disease is a common manifestation in patients with systemic amyloidosis with a number of amyloidogenic proteins discovered in kidney biopsy specimens. The emergence of mass spectrometry-based proteomics has added to the diagnostic accuracy and overall understanding of amyloidosis. This in-depth review discusses the general histopathologic features of renal amyloidosis and includes an in-depth discussion of specific forms of amyloid affecting the kidney.

Hereditary gelsolin amyloidosis

Hereditary gelsolin amyloidosis (HGA) is an autosomally dominantly inherited form of systemic amyloidosis, characterized mainly by cranial and sensory peripheral neuropathy, corneal lattice dystrophy, and cutis laxa. HGA, originally reported from Finland and now increasingly from other countries in Europe, North and South America, and Asia, may still be underdiagnosed worldwide. It is the first and so-far only known disorder caused by a gelsolin gene defect, namely a G654A or G654T mutation. Gelsolin is a principal actin-modulating protein, implicated in multiple biological processes, also in the nervous system, e.g. axonal transport, myelination, neurite outgrowth, and neuroprotection. The gelsolin gene defect causes expression of variant gelsolin, followed by systemic deposition of gelsolin amyloid (AGel) in HGA patients and even other consequences on the metabolism and function of gelsolin. In HGA, specific therapy is not yet available but correct diagnosis enables adequate symptomatic treatment which decisively improves the quality of life in these patients. A transgenic murine model of HGA expressing AGel is available, in anticipation of new treatment options targeted toward this slowly progressive but devastating amyloidosis. Present and future lessons learned from HGA may be applicable even in diagnosis and treatment of other hereditary and sporadic amyloidoses.

Renal amyloidosis associated with a novel sequence variant of gelsolin

We present a case of a 75-year-old woman who presented with progressive kidney failure. Kidney biopsy performed to determine the cause of kidney failure showed amyloidosis of undetermined type. Laser microdissection of the Congo Red-positive glomeruli followed by mass spectrometry studies showed a large number of spectra matching apolipoprotein E, serum amyloid P component, and gelsolin, consistent with a diagnosis of gelsolin-associated renal amyloidosis. Sequencing of the gelsolin gene revealed a previously undescribed sequence variant, a guanine to adenine substitution at nucleotide 580 of the coding sequence, corresponding to a predicted glycine to arginine mutation at amino acid 194. Gelsolin amyloidosis typically involves the nerves and skin, with only rare reported involvement of the kidney. An atypical finding on electron microscopy was that of a swirling pattern of the amyloid fibrils. The novel gelsolin variant may be responsible for the unusual clinical and pathologic presentation. The report also highlights the usefulness of laser microdissection and mass spectrometry in the typing of difficult cases of amyloidosis.