Neurosonographic characteristics of peripheral nerve in transthyretin familial amyloid polyneuropathy / 中华神经科杂志

Objective:To study peripheral nerve morphology in patients with transthyretin familial amyloid polyneuropathy (TTR-FAP) using high-frequency ultrasonography (HFUS), and to evaluate the value of HFUS in diagnosis of TTR-FAP.Methods:Thirty-eight patients with TTR-FAP diagnosed by gene detection and 23 normal controls from June 2015 to June 2021 in Peking University First Hospital were enrolled in this study. Consecutive ultrasonography scanning was performed in 6 pairs of nerves of bilateral limbs with 30 sites. The cross sectional area (CSA), CSA variability and inter-nerve CSA variability data of the two groups were retrospectively calculated and compared.Results:Compared with the normal controls, TTR-FAP patients showed larger CSA values at most nerve sites of both upper and lower limbs, and there were statistically significant differences at M1(median nerve) [8.55 (6.90, 9.40) mm 2vs 10.05 (9.10, 14.10) mm 2, Z=5.58, P<0.001], M3 (median nerve) [(6.98±1.66) mm 2vs (9.29±2.30) mm 2, t=6.28, P<0.001], M5 (median nerve) [(8.91±1.81) mm 2vs (14.33±4.20) mm 2, t=9.84, P<0.001], U5 (ulnar nerve) [(6.20±1.93) mm 2vs (9.34±2.85) mm 2, t=7.31, P<0.001], Sci1 (sciatic nerve) [(53.50±17.24) mm 2vs (79.74±20.75) mm 2, t=7.57, P<0.001], Sci2 (sciatic nerve) [(53.66±14.21) mm 2vs (73.98±19.21) mm 2, t=6.82, P<0.001] and Tib (tibial nerve) [(31.05±8.43) mm 2vs (46.29±13.14) mm 2, t=7.84, P<0.001] sites. There was no statistically significant difference in CSA at each site among the different subtypes and disease severity of TTR-FAP patients ( P>0.05). There was no statistically significant difference in CSA-variability of the median and ulnar nerves between the patients with TTR-FAP and the normal controls ( P>0.05). The side-to-side difference ratio of intra-nerve CSA variability of the ulnar nerve in the patients with TTR-FAP was smaller than that of the normal controls (1.15±0.10 vs 1.46±0.43, t=3.43, P=0.002), whereas no statistically significant difference of that in the median nerve was found between the two groups ( P>0.05). Conclusions:The most pronounced peripheral nerve thickening in the proximal limb segments with no signs of asymmetric distribution or lateralization is confirmed by HFUS in TTR-FAP patients and should be regarded as a marker of TTR-FAP. HFUS has clinical value in diagnosis of peripheral neuropathy in TTR-FAP patients.

Familial amyloid polyneuropathy caused by transthyretin Ala117Ser mutation: a case report and literature review / 中华神经科杂志

Objective:To investigate the clinical manifestations of familial amyloid multiple neuropathy (FAP) caused by Ala117Ser mutation, and to improve the clinical recognition of FAP.Methods:The clinical manifestations, electrophysiological examination, pathology and gene mutation characteristics of a case of FAP, who admitted to Fujian Medical University Union Hospital on November 25, 2014, were analyzed, and the literatures on the FAP cases caused by Ala117Ser mutation were reviewed and summarized.Results:The patient was a 59-year-old male from Fujian province. The first symptom was numbness in the extremities, followed by obvious autonomic nerve symptoms and motor disorder, and fatal cardiac dysfunction occurred in the later stage of the disease. The skin biopsy showed amyloidosis, and transthyretin gene analysis indicated the mutation of c.349G>T p.Ala117Ser. The clinical manifestations of FAP caused by Ala117Ser mutation reported in literatures are consistent with this case. And the reported FAP cases in China are concentrated in southern regions such as Fujian Province and Guangdong Province.Conclusions:Ala117Ser mutation in FAP patients is usually late onset and clinically manifested as multiple sensorimotor peripheral neuropathy, accompanied by prominent autonomic symptoms. The distribution of the patients has significant regional characteristics. Histopathological and genetic tests for the clinical diagnosis are of great significance.

Motivation to perform presymptomatic testing in portuguese subjects at-risk for late-onset genetic diseases

El papel del psicólogo clínico en el contexto del consejo genético incluye brindar apoyo a los sujetos en riesgo en el proceso de toma de decisiones, independientemente de la decisión adoptada por el sujeto (conociendo o no el resultado de las pruebas genéticas). El estudio que se informa aborda la motivación para realizar las pruebas pre-sintomáticas (PPS) de sujetos en situación de riesgo para tres enfermedades: polineuropatía amiloide familiar (PAF), la enfermedad de Huntington (EH) y la enfermedad de Machado-Joseph (EMJ) y comparar con la motivación para realizar las PPS para hemocromatosis (HH). La muestra consistió en 213 sujetos portugueses que tenían riesgo genético para contraer las tres enfermedades y 31 sujetos en situación de riesgo genético para contraer hemocromatosis. Ellos fueron evaluados con una entrevista para obtener datos sociodemográficos y debían responder a una pregunta sobre la motivación para llevar a cabo las pruebas pre-sintomáticas. Se obtuvieron siete categorías principales y las siguientes son las más significativas para PAF, EH y EMJ: razones relacionadas con el futuro, razones relacionadas con los demás y razones relacionadas con la curiosidad y la necesidad de conocer. Para hemocromatosis, las más importantes resultaron ser razones relacionadas con los demás y las relacionadas con las características de la enfermedad. La motivación para realizar el test pre-sintomático (PST) de la PAF, EH y EMJ es externa y sin relación con la enfermedad, mientras que la motivación de los sujetos en situación de riesgo para la HH está relacionada con la enfermedad. Las razones relacionadas con los demás es una motivación común en ambos grupos. A los sujetos también les preocupa la posibilidad de transmitir la enfermedad a sus hijos.

The role of the clinical psychologist in the context of genetic counseling includes support for the process of decision-making for subjects at-risk, regardless of the decision that was made. For this, it is important to know the motivations behind these decisions. What may be considered advant-ageous and justifiable reasons to perform the PST for genetic diseases from the medical and public point of view, i.e., planning for the future, helping in the choice of a profession, family planning, improving quality of life and contributing to health, may not be recognized as such by the individual seeking the PST. This study addresses the motivation to perform the presymptomatic testing (PST) of subjects at-risk for three diseases, Familial Amyloid Polyneuro pathy (FAP), Huntington's disease (HD), and Machado-Joseph disease (MJD), compared with the motivation to perform the PST for Hemochromatosis (HH). FAP, HD and MJD are three genetic (monogenic) autosomal dominant late-onset diseases (LON-Ds) with no cure. FAP is a progressive sensorimotor and autonomic neuropathy of adult hood. HD is characterized by a triad of clinical symptoms of chorea (motor, cognitive and psychiatric symptoms), emotional distress and cognitive decline. MJD is characterized by slowly progressive clumsiness in the arms and legs, a staggering lurching gait, sometimes mistaken for drunkenness, difficulty with speech and swallowing, involuntary eye movements, and may be accompanied by double vision or bulging eyes, and lower limb spasticity. HH is a disease in which too much iron accumulates in parenchymal organs, leading to iron overload and subsequent organ toxicity and failure. The study participants consisted in 213 subjects at genetic risk for FAP, HD, and MJD and 31 subjects at genetic risk for HH, that were assessed through an interview to obtain sociodemographic data and the answer to one question about motivation to perform PST: "Which were the reasons that led you to perform the predictive test? "This study was carried out in Center for Predictive and Preventive Genetics (CGPP), Institute for Molecular and Cell Biology (IBMC), Porto (Portugal). This research used a mixed-method, since qualitative and quantitative techniques of data analysis were used. Before deciding to seek genetic counseling and to know their genetic status, subjects at-risk have naturally considered their motives and it was probably the pro-counseling reasons the ones dictating the motivation to perform the PST. This may suggest that in fact there is a prior self-selection to the test, i.e. only those considering to have emotional skills to go through the process, performing the test. Seven major categories were obtained. The most significant ones for FAP, HD and MJD were reasons related to the future, reasons related to others and reasons related to curiosity and to the need to know. For HH, the most important ones were reasons related to others and reasons related to the characteristics of the disease. The motivation of subjects at-risk to perform the PST for FAP, HD and MJD is external and unrelated to the disease, while the motivation of subjects at-risk to perform the PST for HH is related to the disease. Reasons related to others area common motivation: as subjects at-risk for FAP, HD and MJD, subjects at-risk for HH also chose reasons related to others as one of the most important motivations to carry out the PST. These subjects also care about the fact that they can transmit the disease to their children and care about other family members which are already ill. The category reasons related to others includes sub-categories that identify the person and the situation that led to the decision to perform a PST. Subjects at-risk are also concerned about the fact that they have to decide whether or not to have children and its economic implications.

Presentaciones de polineuropatía amiloidótica familiar asociada a transtiretina en la Argentina / Presentations of transthyretin associated familial amyloid polyneuropathy in Argentina

La polineuropatía amiloidótica familiar asociada a transtiretina (PAF-TTR) es una enfermedad hereditaria con distribución geográfica variable. El objetivo de este trabajo fue presentar nuestra experiencia con pacientes con PAF-TTR. Se evaluaron retrospectivamente 9 casos pertenecientes a diferentes familias. Los criterios diagnósticos utilizados se basaron en la combinación de un cuadro clínico compatible, hallazgos histopatológicos y confirmación genética. Cinco casos mostraron la presentación clásica y 4 la variante de inicio tardío. La mutación p.Val30Met en el gen TTR fue hallada en 6 casos y p.Ala36Pro, p.Thr60Ala y p.Tyr114Cys en los 3 los restantes, respectivamente. La edad media de inicio fue 35 años (rango 26-60). El tiempo medio al diagnóstico fue de 4.2 ± 1.5 años. Siete pacientes recibieron diagnóstico erróneo inicial, 3 de la variante clásica y 4 de la tardía. Nuestra serie de pacientes mostró marcada heterogeneidad en la presentación clínica del grupo de PAF-TTR de inicio tardío, en una región no endémica de Sudamérica.

Transthyretin-related familial amyloid polyneuropathy (TTR-FAP) is a hereditary disease with variable geographical distribution. The aim of this study was to present our experience with TTR-FAP patients. We retrospectively analyzed nine cases belonging to different families. Diagnostic criteria were based on the combination of compatible clinical picture, histopathological findings and genetic confirmation. Five cases showed the classic presentation and other 4 the late onset variant. The p.Val30Met mutation in the TTR gene was found in 6 cases and p.Ala36Pro, p.Thr60Ala and p.Tyr114Cys in the remaining 3, respectively. The median age of symptom onset was 35 years (26-60 range). Mean time to diagnosis was 4.2 ± 1.5 years. Our patient series showed the heterogeneity in clinical presentation of TTR-FAP in a non-endemic region of South America.

Orthotopic Liver Transplantation in Glycogen Storage Disease Type 1a: Perioperative Glucose and Lactate Homeostasis

Abstract Glycogen storage disease type 1a (GSD 1a) is a rare inborn error of metabolism. It causes severe fasting intolerance and lactic acidosis due to the deficiency of glucose-6-phosphatase enzyme. Blood glucose and lactate concentrations from 2 patients with GSD 1a were retrospectively compared to a control group of patients with familial amyloid polyneuropathy. Carbohydrate intake and infusions were compared to experimental data based on stable isotope studies. Perioperative lactate concentrations were significantly higher in our 2 patients with GSD 1a (median 15.0 mmol/L; range 9.9-22.0 mmol/L) versus 8 controls. In one patient, despite normal blood glucose concentrations, lactate acidosis was probably caused by a combination of the disease itself, insufficient (par)enteral carbohydrate intake, Ringer lactate infusions, and circulatory insufficiency. Patients with GSD 1a carry an increased risk of lactic acidosis during orthotopic liver transplantation compared to non-GSD patients. Multidisciplinary perioperative care is essential to prevent significant complications.