Orthopaedic Manifestations of Amyloidosis

Wild-type transthyretin cardiac amyloidosis is not rare in elderly subjects: the CATCH screening study

AIMS

Wild-type transthyretin cardiac amyloidosis (ATTRwt-CA) affects older adults and is currently considered as a rare disorder. We investigated for the first time the prevalence of ATTRwt-CA in elderly individuals from the general population.

METHODS AND RESULTS

General practitioners from Pisa, Italy, proposed a screening for ATTRwt-CA to all their patients aged 65-90 years, until 1000 accepted. The following red flags were searched: interventricular septal thickness ≥ 12 mm, any echocardiographic, electrocardiographic or clinical hallmark of CA, or high-sensitivity troponin T ≥ 14 ng/L. Individuals with at least one red flag (n = 346) were asked to undergo the search for a monoclonal protein and bone scintigraphy, and 216 accepted. Four patients received a non-invasive diagnosis of ATTRwt-CA. All complained of dyspnoea on moderate effort. A woman and a man aged 79 and 85 years, respectively, showed an intense cardiac tracer uptake (Grade 3), left ventricular (LV) wall thickening, Grade 2 and 3 diastolic dysfunction, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) > 1000 ng/L. Two other patients (a man aged 74 years and a woman aged 83 years) showed a Grade 2 uptake, an increased LV septal thickness, but preserved diastolic function, and NT-proBNP < 300 ng/L. The prevalence of ATTR-CA in subjects ≥ 65 years was calculated as 0.46% (i.e. 4 out of the 870 subjects completing the screening, namely 654 not meeting the criteria for Step 2 and 216 progressing to Step 2).

CONCLUSION

Wild-type transthyretin cardiac amyloidosis is uncommon in elderly subjects from the general population, but more frequent than expected for a rare disease.

Early Diagnosis of Amyloidosis and Cardiac Involvement through Carpal Tunnel Surgery and Predictive Factors

Background/Objectives: To determine the prevalence of amyloidosis through the analysis of synovial tissue and transverse carpal ligament (TCL) in patients undergoing surgery for carpal tunnel syndrome (CTS), detect predictive factors for the presence of amyloid, and assess cardiac involvement degree. Methods: A prospective study with longitudinal cohort follow-up at a teaching hospital. Patients undergoing CTS surgery from 1 January 2019 to 31 May 2021 were included. Samples from synovial and TCL tissues were examined for amyloid presence. Multivariate analysis was used to detect predictive factors of the presence of amyloid. Patients with amyloid underwent echocardiography, laboratory analyses, and scintigraphy. Results: Two hundred and forty-six patients were included. The prevalence of amyloid was 11.4% in TCL and 12.6% in synovial tissues. Age (p = 0.035; OR 1.123), bilateral CTS symptoms (p = 0.022; OR 3.647), and trigger finger (p < 0.001; OR 3.537) were predictors of the presence of amyloid. Seventeen patients were diagnosed with transthyretin amyloidosis (ATTR) located in the carpus (no scintigraphic cardiac uptake or grade 0), one with light chain amyloidosis, eight with ATTR with cardiac involvement (grades 2-3), and five with ATTR in the carpus and scintigraphic uptake grade 1 (with normal echocardiogram and blood and urine tests). Conclusions: We detected amyloid in 12.6% of unselected consecutive patients who underwent CTS surgery. Biopsy in patients with CTS for amyloid detection, especially in elderly patients with bilateral symptoms and trigger finger, may be useful for the early diagnosis of amyloidosis, primarily due to transthyretin.

A Comparison of Tenosynovial and Transverse Carpal Ligament Biopsy for Amyloid Detection in Open Carpal Tunnel Release

PURPOSE

Our purpose was to compare differences in the incidence of amyloid deposition in tenosynovium (TS) versus transverse carpal ligament (TCL) biopsies obtained during open carpal tunnel release. We hypothesized that the incidence of amyloid would be similar between TCL and TS when obtaining both specimens from the same patient.

METHODS

All primary, elective open carpal tunnel release cases that underwent biopsy for amyloid between January 2022 and September 2023 were reviewed. Tenosynovial and TCL specimens were independently evaluated by a pathologist to assess for amyloid. Demographic data were collected, and incidence of amyloid deposition was compared between the two samples. Agreement statistics, sensitivity, and specificity were calculated for TCL, using TS as the reference standard.

RESULTS

A total of 196 cases met either Tier 1 (n=180) or Tier 2 (n=16) biopsy criteria. Forty-eight cases were excluded for missed biopsies or laboratory processing errors, leaving 148 cases available for analysis. Amyloid deposition was present in 31 out of 148 (21%) TS specimens and 33 out of 148 (22%) TCL specimens. Overall, the results of the TS biopsy agreed with TCL biopsy in 138 out of 148 cases (93%). In the 10 cases for which the results of the TCL and TS biopsy differed, six cases had (+) TCL and (-) TS, and four cases had amyloid deposition in TS without evidence of deposition in the TCL. Sensitivity and specificity values for the TCL specimen were 87% and 95%, respectively. Positive and negative predictive values were 82% and 97%, respectively.

CONCLUSIONS

For cases of open carpal tunnel release undergoing biopsy, amyloid deposition was noted in 21% of TS specimens and 22% of TCL specimens. Results of TS and TCL biopsies obtained from the same patient agreed in 93% of cases. Single-source biopsy for amyloid represents a reasonable diagnostic approach. Future cost analyses should be performed to determine whether the addition of two biopsy sources to improve diagnostic accuracy is justified.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Ultrasound findings of the sternoclavicular and shoulder joints in patients on maintenance hemodialysis

INTRODUCTION

Ultrasonographic examination of joints is a non-invasive method to detect and monitor Dialysis-associated amyloidosis (DRA).

METHODS

An ultrasonographic examination of the sternoclavicular (SC) and shoulder joints was performed in patients on maintenance hemodialysis (MHD) and those with normal renal function in the control group. The maximum distance (D) of SC, the rotator cuff thickness (RCs), and the echogenic pads (EPs) of the shoulder were evaluated.

RESULTS

Compared with the control group, the MHD group had a higher D of SC, a higher proportion of RCs ≥8 mm, and a higher proportion of EPs positive. Adjust for age and Kt/V, the D of SC was positively related to dialysis vintage, standardized coefficients β = 0.329, p = 0.004. A significant positive correlation existed between the D of SC and the RCs.

CONCLUSION

In addition to the shoulder joint, the sternoclavicular is a suitable site for ultrasonographic detection of DRA.

A Comparison of Amyloid Deposition in Endoscopic and Open Carpal Tunnel Release

PURPOSE

Previous investigations assessing the incidence of amyloidosis detected with biopsy during carpal tunnel release (CTR) have focused on open CTR (OCTR). Prior authors have suggested that biopsy may be more technically challenging during endoscopic carpal tunnel release (ECTR). Our purpose was to compare differences in the incidence of amyloid deposition detected during ECTR versus OCTR.

METHODS

We reviewed all primary ECTR and OCTR during which a biopsy for amyloid was obtained between February 2022 and June 2023. All procedures were performed by five upper-extremity surgeons from a single institution. Congo red staining was used to determine the presence of amyloid deposition in either the transverse carpal ligament (TCL) or tenosynovium. All positive cases underwent subtype analysis and protein identification through liquid chromatography-tandem mass spectrometry. Baseline demographics were recorded for each case, and the incidence of positive biopsy was compared between ECTR and OCTR cases.

RESULTS

A total of 282 cases were included for analysis (143 ECTR and 139 OCTR). The mean age was 67 years, and 45% of cases were women. Baseline demographics were similar except for a significantly higher incidence of diabetes in OCTR cases (13% vs 33%). Overall, 13% of CTR cases had a positive biopsy. There was a statistically significant difference in the incidence of amyloid deposition detected during biopsy in ECTR cases (3.5%) compared with OCTR cases (23%).

CONCLUSIONS

Biopsy performed during ECTR may result in a lower incidence of amyloid detection. Future basic science investigation may be necessary to determine histologic differences between tenosynovium proximal and distal to the leading edge of the TCL. When surgeons plan a biopsy during surgical release of the carpal tunnel, an open approach may be advantageous.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Amyloidosis and Considerations for the Hand Surgeon

Amyloidosis can lead to cardiac, renal, and other multiorgan failure. New treatments have become available that can prolong survival but rely on early diagnosis. Manifestations of amyloidosis in hand surgery include carpal tunnel syndrome, trigger finger, peripheral neuropathy, and spontaneous distal biceps rupture. Often, these can predate systemic amyloidosis, offering hand surgeons an opportunity to diagnose patients with amyloidosis before systemic disease, refer them for treatment, and potentially alter disease course and prolong survival. In this review, we describe the pathophysiology and two most common subtypes of amyloidosis seen by hand surgeons. We provide guidance on biopsy practices and referral for patients with amyloidosis. Lastly, we provide a brief overview of the treatments for amyloidosis and their effect on disease course.

Musculoskeletal manifestations associated with transthyretin-mediated (ATTR) amyloidosis: a systematic review

BACKGROUND

Hereditary and wild-type transthyretin-mediated (ATTRv and ATTRwt) amyloidoses result from the misfolding of transthyretin and aggregation of amyloid plaques in multiple organ systems. Diagnosis of ATTR amyloidosis is often delayed due to its heterogenous and non-specific presentation. This review investigates the association of musculoskeletal (MSK) manifestations with ATTR amyloidosis and the delay from the onset of these manifestations to the diagnosis of ATTR amyloidosis.

METHODS

This systematic review utilized Medline and EMBASE databases. Search criteria were outlined using a pre-specified patient, intervention, comparator, outcome, time, study (PICOTS) criteria and included: amyloidosis, ATTR, and MSK manifestations. Publication quality was assessed utilizing Joanna Briggs Institute (JBI) critical appraisal checklists. The search initially identified 7,139 publications, 164 of which were included. PICOTS criteria led to the inclusion of epidemiology, clinical burden and practice, pathophysiology, and temporality of MSK manifestations associated with ATTR amyloidosis. 163 publications reported on ATTR amyloidosis and MSK manifestations, and 13 publications reported on the delay in ATTR amyloidosis diagnosis following the onset of MSK manifestations.

RESULTS

The MSK manifestation most frequently associated with ATTR amyloidosis was carpal tunnel syndrome (CTS); spinal stenosis (SS) and osteoarthritis (OA), among others, were also identified. The exact prevalence of different MSK manifestations in patients with ATTR amyloidosis remains unclear, as a broad range of prevalence estimates were reported. Moreover, the reported prevalence of MSK manifestations showed no clear trend or distinction in association between ATTRv and ATTRwt amyloidosis. MSK manifestations precede the diagnosis of ATTR amyloidosis by years, and there was substantial variation in the reported delay to ATTR amyloidosis diagnosis. Reports do suggest a longer diagnostic delay in patients with ATTRv amyloidosis, with 2 to 12 years delay in ATTRv versus 1.3 to 1.9 years delay in ATTRwt amyloidosis.

CONCLUSION

These findings suggest that orthopedic surgeons may play a role in the early diagnosis of and treatment referrals for ATTR amyloidosis. Detection of MSK manifestations may enable earlier diagnosis and administration of effective treatments before disease progression occurs.

Amyloidosis of the Femoral Neck: An Unusual Cause of Pathologic Fracture

The deposition of amyloid within human tissue can be detrimental to the proper functioning of multiple organ systems. While the infiltration of the amyloid protein within the musculoskeletal soft tissues can lead to compressive neuropathies, tendon irritation or rupture, and joint stiffness, pathologic fracture as a result of amyloid deposition in bone is a rare manifestation of amyloidosis. We present a case of pathologic fracture of the femoral neck from amyloid deposition in a 59-year-old male on chronic hemodialysis who was found to have lytic lesions in his proximal femur. At the time of hemiarthroplasty, histopathologic analysis of a femoral head sample revealed apple-green birefringence of the deposits under polarized light, consistent with amyloid deposition. Clinicians should have a high index of suspicion for the atypical presentation of amyloidosis in a patient on chronic hemodialysis with lytic bone lesions.

Clinical relevance of amyloid in prostate samples: a report on 40 patients

OBJECTIVE

To describe the clinical findings in patients with incidental prostatic amyloidosis.

PATIENTS AND METHODS

Retrospective search in the database of the Department of Pathology, Hospital de Bellvitge, for prostate specimens with amyloid. Congo red and immunohistochemical staining of the sections. Review of the patients' clinical charts for symptoms attributable to systemic amyloidosis.

RESULTS

Amyloid deposition in the prostate was identified and reported in 40 patients between 2001 and 2022. Median age was 76.5 years (range 62-90). Prostate cancer was diagnosed in 25 patients. Only 4 patients had a previous diagnosis of amyloidosis. In the remaining 36 the prostate sample (31 needle biopsies, two transurethral resections (TUR), two simple prostatectomies, one radical cystectomy for bladder cancer) provided the initial diagnosis. Amyloid deposits were mainly located in the wall of small vessels and rarely in the prostatic stroma. Immunohistochemistry was available in 32 cases, 26 of which were positive for TTR. All patients showed at least one symptom indicative of systemic amyloidosis, the most frequent being hearing loss (55%), carpal tunnel syndrome (42,5%) or other osteoarticular symptoms (tendinopathies, osteoarthritis), cataracts (37.5%), and cardiac symptoms (32.5%), among others.

CONCLUSION

The prostate is a target tissue for amyloid deposition. The incidental finding of amyloid in prostate corresponds, in the majority of cases, to previously undiagnosed systemic TTR amyloidosis in patients lacking signs of heart involvement but having mainly osteoarticular symptoms, hearing and visual impairment.

Supportive Care and Symptom Management for Patients With Immunoglobulin Light Chain (AL) Amyloidosis

Immunoglobulin light chain (AL) amyloidosis is a disorder of clonal plasma cells characterized by deposition of amyloid fibrils in a variety of tissues, leading to end-organ injury. Renal or cardiac involvement is most common, though any organ outside the central nervous system can develop amyloid deposition, and symptomatic presentations may consequently vary. The variability and subtlety of initial clinical presentations may contribute to delayed diagnoses, and organ involvement is often quite advanced and symptomatic by the time a diagnosis is established. Additionally, while organ function can improve with plasma-cell-directed therapy, such improvement lags behind hematologic response. Consequently, highly effective supportive care, including symptom management, is essential to improve quality of life and to maximize both tolerance of therapy and likelihood of survival. Considering the systemic nature of the disease, close collaboration between clinicians is essential for effective management.

Risk of Amyloidosis and Heart Failure Among Patients Undergoing Surgery for Trigger Digit or Carpal Tunnel Syndrome: A Nationwide Cohort Study With Implications for Screening

PURPOSE

Tenosynovial biopsy during carpal tunnel release (CTR) leads to an earlier diagnosis of amyloidosis. Surgery for trigger digit-trigger release (TR)-may provide a similar opportunity. We sought to characterize the risk of amyloidosis diagnosis after TR and/or CTR.

METHODS

We conducted a retrospective cohort study of adults without diagnosed amyloidosis undergoing TR and/or CTR in the Veterans Health Administration from 1999 to 2019, including matched controls. We used competing-risks methodology to estimate the cumulative incidence and adjusted subdistribution hazard ratios (sHRs) of amyloidosis, heart failure, and death after TR and/or CTR.

RESULTS

Among the 126,788 patients undergoing TR and/or CTR, amyloidosis was diagnosed in 52 of 26,757 patients undergoing TR alone at a median of 4.7 years after surgery (10-year cumulative incidence: 0.26%, 95% CI: 0.18% to 0.34%), 396 of 91,384 patients undergoing CTR alone at a median of 5.1 years after surgery (10-year cumulative incidence: 0.60%, 95% CI: 0.53% to 0.67%), 50 of 8,647 patients undergoing both TR and CTR at a median of 3.1 years after surgery (10-year cumulative incidence: 0.80%, 95% CI: 0.54% to 1.1%), and 54 of 113,452 controls at a median of 5.0 years after the index date (10-year cumulative incidence 0.053%, 95% CI: 0.037% to 0.070%). In the adjusted analysis, patients who underwent TR and/or CTR had a higher risk of amyloidosis (TR: sHR_adj 4.80, 95% CI: 3.33-6.92; CTR: sHR_adj 10.2, 95% CI: 7.74-13.6; TR and CTR: sHR_adj 14.9, 95% CI: 9.87-22.5) and heart failure (TR: sHR_adj 1.91, 95% CI: 1.83-1.99; CTR: sHR_adj 2.02, 95% CI: 1.97-2.07; TR and CTR: sHR_adj 2.18, 95% CI: 2.04-2.33) but not death compared with the controls. Among the patients who underwent TR, age, Black race, prior CTR, heart failure, and the number of digits released were independent risk factors for amyloidosis.

CONCLUSIONS

Patients undergoing TR and/or CTR are at increased risk of incident amyloidosis and heart failure compared to controls.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Prevalence and Subtypes of Tenosynovial Amyloid in Patients Undergoing Carpal Tunnel Release

PURPOSE

The purpose of this study was to determine the prevalence and subtypes of amyloid in tenosynovial biopsies of patients undergoing carpal tunnel release (CTR).

METHODS

A retrospective review was performed involving patients who underwent CTR from June 2020 to July 2021. Prior to this period, a protocol had been established to obtain routine intraoperative tenosynovial biopsies. Tenosynovium was preserved in formalin and stained with Congo red for amyloid. Positive specimens were sent to an external laboratory for confirmation and subtyping by mass spectrometry. Men 50 years or older and women 60 or older were included for analysis. Acute, traumatic, and revision cases were excluded.

RESULTS

Of 185 patients who underwent CTR with tenosynovial biopsy, 54 (29%) demonstrated positive Congo red stain, confirmed by the external laboratory. A subtype analysis revealed wild-type transthyretin (TTR) in 44 patients (80%), mixed wild-type TTR with κ light chains in 1 patient, and hereditary TTR in 1 patient. Patients with positive specimens were significantly older than those who tested negative (77 vs 68 years, respectively), and positivity increased by decade for both sexes. Male sex, atrial fibrillation, and spinal stenosis were significantly more prevalent among positive cases. There were no complications from the biopsies.

CONCLUSIONS

We confirmed evidence of amyloidosis in the tenosynovium of 29% of men 50 years or older and women 60 or older who underwent CTR. The majority demonstrated wild-type TTR. As these patients are at risk of developing cardiomyopathy, there is an opportunity for early detection, monitoring, and interventions known to improve outcomes. Considering the low cost of Congo red staining and the potential value of subtyping with regard to treatment of cardiomyopathy, our findings support routine tenosynovial biopsy during CTR in patients who meet the age criteria.

TYPE OF STUDY/LEVEL OF EVIDENCE

Differential diagnosis or symptom prevalence study II.