Role of autonomic nerve functions in patients with familial amyloidotic polyneuropathy as analyzed by laser Doppler flowmetry, capsule hydrograph, and cardiographic R-R interval

Assessment of autonomic nervous system dysfunction associated with peripheral neuropathies in the context of clinical neurophysiology practice

Peripheral neuropathies may involve the small diameter nerve fibers of the autonomic nervous system. In the presence of clinical signs compatible with dysautonomia, it is very difficult to affirm that these signs are really linked to an alteration in postganglionic autonomic innervation, and not to a lesion of the central nervous system or to a direct damage to the tissues and innervated organs. Also, in the context of the investigation of peripheral neuropathies, there is an interest in performing objective and quantitative assessment of distal autonomic innervation. The corresponding autonomic tests are mainly based on the exploration of sudomotor or vasomotor disorders of the limb extremities. In this article, we provide an overview of the various tests available for the study of the autonomic nervous system in clinical practice, including vasomotor reactivity tests, in particular based on laser Doppler techniques, and sudomotor tests, based on axon-reflexes produced by iontophoresis of cholinergic drugs or on the simpler measurement of electrochemical skin conductance by the Sudoscan® device.

Avoiding misdiagnosis: expert consensus recommendations for the suspicion and diagnosis of transthyretin amyloidosis for the general practitioner

BACKGROUND

Transthyretin amyloidosis (also known as ATTR amyloidosis) is a systemic, life-threatening disease characterized by transthyretin (TTR) fibril deposition in organs and tissue. A definitive diagnosis of ATTR amyloidosis is often a challenge, in large part because of its heterogeneous presentation. Although ATTR amyloidosis was previously considered untreatable, disease-modifying therapies for the treatment of this disease have recently become available. This article aims to raise awareness of the initial symptoms of ATTR amyloidosis among general practitioners to facilitate identification of a patient with suspicious signs and symptoms.

METHODS

These consensus recommendations for the suspicion and diagnosis of ATTR amyloidosis were developed through a series of development and review cycles by an international working group comprising key amyloidosis specialists. This working group met to discuss the barriers to early and accurate diagnosis of ATTR amyloidosis and develop a consensus recommendation through a thorough search of the literature performed using PubMed Central.

RESULTS

The cardiac and peripheral nervous systems are most frequently involved in ATTR amyloidosis; however, many patients often also experience gastrointestinal and other systemic manifestations. Given the multisystemic nature of symptoms, ATTR amyloidosis is often misdiagnosed as a more common disorder, leading to significant delays in the initiation of treatment. Although histologic evaluation has been the gold standard to confirm ATTR amyloidosis, a range of tools are available that can facilitate early and accurate diagnosis. Of importance, genetic testing should be considered early in the evaluation of a patient with unexplained peripheral neuropathy.

CONCLUSIONS

A diagnostic algorithm based on initial red flag symptoms and manifestations of cardiac or neurologic involvement will facilitate identification by the general practitioner of a patient with clinically suspicious symptoms, enabling subsequent referral of the patient to a multidisciplinary specialized medical center.

Excisional goniotomy with Kahook Dual Blade in a patient with glaucoma secondary to Transthyretin Amyloidosis

PURPOSE

To report for the first time the successful use of the Kahook Dual Blade excisional goniotomy technique in a patient with Transthyretin Amyloidosis.

PATIENT AND METHODS

The Kahook Dual Blade is a single use ab interno trabeculectomy device that removes the trabecular meshwork reducing aqueous humor outflow resistance. A patient with Transthyretin Amyloidosis underwent this procedure.

RESULTS

Ab interno goniotomy with Kahook Dual Blade was a successful surgical solution to reduce intraocular pressure in a patient with Transthyretin Amyloidosis secondary glaucoma controlling IOP in association with topical hypotensors for at least 6 months.

CONCLUSIONS

Ab interno goniotomy with Kahook Dual Blade is a surgical option for this type of glaucoma, that treats the main site of aqueous outflow resistance in this pathology with the advantage of being minimally invasive.

Orthostatic hypotension in hereditary transthyretin amyloidosis: epidemiology, diagnosis and management

Purpose

Neurogenic orthostatic hypotension is a prominent and disabling manifestation of autonomic dysfunction in patients with hereditary transthyretin (TTR) amyloidosis affecting an estimated 40–60% of patients, and reducing their quality of life. We reviewed the epidemiology and pathophysiology of neurogenic orthostatic hypotension in patients with hereditary TTR amyloidosis, summarize non-pharmacologic and pharmacological treatment strategies and discuss the impact of novel disease-modifying treatments such as transthyretin stabilizers (diflunisal, tafamidis) and RNA interference agents (patisiran, inotersen).

Methods

Literature review.

Results

Orthostatic hypotension in patients with hereditary transthyretin amyloidosis can be a consequence of heart failure due to amyloid cardiomyopathy or volume depletion due to diarrhea or drug effects. When none of these circumstances are apparent, orthostatic hypotension is usually neurogenic, i.e., caused by impaired norepinephrine release from sympathetic postganglionic neurons, because of neuronal amyloid fibril deposition.

Conclusions

When recognized, neurogenic orthostatic hypotension can be treated. Discontinuation of potentially aggravating medications, patient education and non-pharmacologic approaches should be applied first. Droxidopa (Northera^®), a synthetic norepinephrine precursor, has shown efficacy in controlled trials of neurogenic orthostatic hypotension in patients with hereditary TTR amyloidosis and is now approved in the US and Asia. Although they may be useful to ameliorate autonomic dysfunction in hereditary TTR amyloidosis, the impact of disease-modifying treatments on neurogenic orthostatic hypotension is still uninvestigated.

Assessment of autonomic innervation of the foot in familial amyloid polyneuropathy

BACKGROUND AND PURPOSE

Distal involvement of autonomic nerve fibers is critical in familial amyloid polyneuropathy (FAP) due to transthyretin (TTR) mutation. This study compares different methods for assessing autonomic foot innervation in TTR-FAP patients.

METHODS

Three groups of seven TTR-FAP patients were included, according to disease severity: clinically asymptomatic, moderate or advanced neuropathy. The autonomic investigation included the eutectic mixture of local anesthetics test and laser Doppler flowmetry for vasomotor aspects and the Sudoscan® (measuring electrochemical skin conductance) and Neuropad® test for sudomotor aspects. Somatic innervation was assessed by performing nerve conduction studies, quantitative sensory testing [including vibration, cold and warm detection threshold (WDT) measurements] and laser evoked potentials.

RESULTS

The results of all neurophysiological tests varied according to TTR-FAP severity (P ≤ 0.01, Kruskal-Wallis test), except for the eutectic mixture of local anesthetics test and laser Doppler flowmetry variables. In addition, the sudomotor tests (Sudoscan or Neuropad) or WDT measurement provided early markers of neuropathy in two of the seven asymptomatic carriers. Finally, all neurophysiological results correlated with the Neuropathy Impairment Score (r values between -0.88 and -0.66, P < 0.005, Spearman test), except the cold detection threshold.

CONCLUSIONS

The Neuropad test could be used to detect TTR-FAP onset, but confirmation requires electrochemical skin conductance and WDT measurement. The Sudoscan technique, but not the Neuropad test (at least assessed at a fixed time point), could be valuable to follow the progression of the neuropathy. Follow-up investigation should also include large-fiber investigation (e.g. nerve conduction studies and vibration detection threshold). Conversely, reliable tests for assessing vasomotor disturbances in limb extremities of TTR-FAP patients are still awaited.

[Diagnosis of small-fiber neuropathy using various autonomic function tests]

It is well known that transthyretin-related familial amyloidotic polyneuropathy (TTR-FAP) and diabetic peripheral neuropathy are characterized by early selective involvement of small nerve fibers. However, early diagnosis of these diseases is not easy because prominent early diagnostic markers for small fiber neuropathies have not established. Thus, we adopted several methods to evaluate autonomic function accurately for detecting the onset of small-fiber neuropathy, such as laser-Doppler flowmetry, sweating tests using capsule type sweating ratemeter, morphological check of sweat gland, electrogastrography, density check of small-fiber and gastrointestinal interstitial cells of Cajal, R-R interval study, (123)I-MIBG myocardial scintigraphy, and head-up tilt test to check the overshoot phenomenon. These tests may indicate very early stage of small-fiber neuropathies in asymptomatic mutated TTR carriers or impaired glucose tolerance patients. Moreover, assessment of the pain thresholds by preferential stimulation of C and Aδ fibers are particularly useful tools for diagnosing the onset of small-fiber neuropathies in addition to the autonomic testing.

Sudomotor innervation in transthyretin amyloid neuropathy: Pathology and functional correlates

OBJECTIVE

Autonomic neuropathy is a major component of familial amyloid polyneuropathy (FAP) due to mutated transthyretin, with sudomotor failure as a common manifestation. This study aimed to investigate the pathology and clinical significance of sudomotor denervation.

METHODS

Skin biopsies were performed on the distal leg of FAP patients with a follow-up duration of 3.8 ± 1.6 years. Sudomotor innervation was stained with 2 markers: protein gene product 9.5 (PGP 9.5), a general neuronal marker, and vasoactive intestinal peptide (VIP), a sudomotor nerve functional marker, followed by quantitation according to sweat gland innervation index (SGII) for PGP 9.5 (SGIIPGP 9.5) and VIP (SGIIVIP).

RESULTS

There were 28 patients (25 men) with Ala97Ser transthyretin and late onset (59.9 ± 6.0 years) disabling neuropathy. Autonomic symptoms were present in 22 patients (78.6%) at the time of skin biopsy. The SGIIPGP 9.5 and SGIIVIP of FAP patients were significantly lower than those of age- and gender-matched controls. The reduction of SGIIVIP was more severe than that of SGIIPGP 9.5 (p = 0.002). Patients with orthostatic hypotension or absent sympathetic skin response at palms were associated with lower SGIIPGP 9.5 (p = 0.019 and 0.002, respectively). SGIIPGP 9.5 was negatively correlated with the disability grade at the time of skin biopsy (p = 0.004), and was positively correlated with the interval from the time of skin biopsy to the time of wheelchair usage (p = 0.029).

INTERPRETATION

This study documented the pathological evidence of sudomotor denervation in FAP. SGIIPGP 9.5 was functionally correlated with autonomic symptoms, autonomic tests, ambulation status, and progression of disability.

Comparable accuracy of micro-electromechanical blood flowmetry-based analysis vs. electrocardiography-based analysis in evaluating heart rate variability

BACKGROUND

Because the conventional evaluation of autonomic nervous system (ANS) function inevitably uses long-lasting uncomfortable electrocardiogram (ECG) recording, a more simplified and comfortable analysis system has been sought for this purpose. The feasibility of using a portable micro-electromechanical system (MEMS) blood flowmeter to analyze heart rate variability (HRV) for evaluating ANS function was thus examined.

METHODS AND RESULTS

Measurements of the R-R interval (TRR) derived from an ECG, simultaneously with the pulse wave interval (TPP) derived from a MEMS blood flowmeter, in 8 healthy subjects was performed and resultant HRV variables in time and frequency domains were compared. The TRR- and TPP-derived variables were strongly correlated (coefficients of regression for low frequency (LF), high frequency (HF), and LF/HF of 1.1, 0.66, and 0.35, respectively; corresponding coefficients of determination of 0.92, 0.63, and 0.91, respectively (P<0.01)). In addition, the values of LF, HF, and LF/HF, as analyzed using TPP, changed significantly from the supine to the standing position in another 6 subjects.

CONCLUSIONS

Miniaturized-MEMS blood flowmetry can be used to perform HRV analysis for the evaluation of ANS function, which is as accurate as analysis based on ECG within comparable tolerances. As MEMS blood flowmetry can more easily and comfortably record physiological variables for longer durations than ECG recording, and can further capture skin blood flow information, this device has great potential to be used in a wider area of physiological analyses.

Focus on autonomic dysfunction in familial amyloidotic polyneuropathy (FAP)

It is well known that autonomic dysfunction in familial amyloidotic polyneuropathy (FAP) is the most serious problem, because it restricts the daily life of these patients. The detail mechanisms of the onset are not well understood in FAP and domino liver transplantation-induced amyloid neuropathy. As autonomic disturbances play an important role in the symptomatology of FAP, further studies of autonomic dysfunction in these patients may lead the pathogenesis of FAP. Autonomic dysfunction is often observed before sensory and motor nerve dysfunction in FAP. This can be attributed to the morphological characteristics of the nerves. Unmyelinated, small myelinated, and large myelinated fibers tend to become impaired in that order. Although the reasons of susceptibility to amyloid infiltration and injury are not known, studies of autopsied FAP patients have revealed heavy infiltration of amyloid in autonomic ganglions. Moreover, spinal ganglion and posterior loot of the spine had severe amyloid deposits than did the anterior root of the spine or the motor nerves. It is well known that autonomic dysfunction is the most serious problem, because it restricts the daily life of FAP patients. However, we have four major questions about autonomic dysfunction in clinical. In this manuscript, we discuss about the answers of these questions.

Clinical features of TTR-FAP in Portugal

Familial amyloid polyneuropathy (FAP) is an autosomal dominant disorder characterized by the extracellular deposition of transthyretin (TTR) fibrils in several tissues, particularly in the peripheral nervous system. The largest focus of the disease is in Portugal where the age of disease onset shows a wide range (17-78 years), with 80% of cases developing symptoms before age 40. The characteristic fiber length-dependent sensory-motor and autonomic neuropathy are the neurological hallmark of TTR-FAP. Additional cardiovascular, gastrointestinal (GI), renal and ocular symptoms are the main systemic manifestations that account for phenotypic heterogeneity.

Patterns of neuropathy and autonomic failure in patients with amyloidosis

OBJECTIVE

To define the clinical patterns of peripheral neuropathy and autonomic testing abnormalities in patients with amyloidosis.

PATIENTS AND METHODS

A retrospective chart review was conducted of 65 patients who had biopsy-proven amyloidosis and autonomic function testing between January 1, 1985, and December 31, 1997, at Mayo Clinic's site in Rochester, MN. Patients were required to have neurologic evaluation, autonomic reflex screening, and tissue confirmation of amyloidosis.

RESULTS

We identified 5 clinical patterns of peripheral neuropathy: (1) generalized autonomic failure and polyneuropathy with pain (40 patients [62%]), (2) generalized autonomic failure and polyneuropathy without pain (11 [17%]), (3) isolated generalized autonomic failure (7 [11%]), (4) polyneuropathy without generalized autonomic failure (4 [6%]), and (5) generalized autonomic failure and small-fiber (ie, autonomic and somatic C-fiber) neuropathy (3 [5%]). Moderately severe generalized autonomic failure, involving adrenergic, cardiovagal, or sudomotor domains, was found in all patients, including those without clinically manifested autonomic failure. The diagnosis of amyloidosis was delayed in patients who did not have initial symptoms of pain or generalized autonomic failure (48 months to diagnosis in patients with polyneuropathy without autonomic failure vs 12 months to diagnosis in patients with autonomic failure and small-fiber neuropathy; P=.57).

CONCLUSION

Physicians should test for symptoms of generalized autonomic failure in patients who have peripheral neuropathy of unknown origin. Autonomic testing may give abnormal results in patients without overt symptoms of autonomic failure. Early recognition of autonomic failure may lead to earlier diagnosis of the underlying pathogenesis of amyloidosis, as well as earlier treatment for patients with this condition.

Transthyretin amyloidosis in a patient of Iranian-Jewish extraction: a second Israeli-Jewish case

BACKGROUND

We present a patient with late-onset progressive polyneuropathy and a Congo-red positive staining of sural nerve biopsy, where routine immunohistochemical analysis failed to determine the type of amyloid deposited. Since precise determination of the amyloid type has crucial therapeutic implications, we employed our new biochemical micro-techniques, together with molecular biology methods, to characterize the amyloid protein deposited.

METHODS

We used a micro-method for extraction of amyloid proteins, amyloid typing by Western blotting, DNA sequencing, and restriction enzyme site analysis.

RESULTS

Our new micro-technique for biochemical analysis of fat aspirate demonstrated transthyretin (TTR) amyloid (ATTR) deposition in the patient's tissue. Sequence analysis of the TTR-encoding DNA identified a single mutation, causing a valine to alanine substitution (V32A).

CONCLUSIONS

Although there are approximately 100 known TTR variants associated with peripheral neuropathy, in Israel only one patient with familial amyloid polyneuropathy (FAP), a patient of Ashkenazi origin with ATTR due to an F33I mutation, has been reported so far. Our study identified a second case of ATTR in the Israeli population, this time in a patient of Iranian-Jewish extraction. The study also emphasizes the importance of our new biochemical micro-techniques in elucidating the type of amyloid protein.

Skin vasomotor reflex responses in two contrasting groups of autonomic failure

BACKGROUND & AIM

A variety of stimuli such as deep inspiration, isometric exercise and mental arithmetic, result in a transient vasoconstriction,mediated by sympathetic efferent nerves, in the skin of the fingers and toes of healthy controls (Skin Vasomotor Reflex: SkVR). Multiple system atrophy (MSA) and pure autonomic failure (PAF) provide contrasting models of autonomic failure. In MSA the lesion is central and preganglionic, whilst in PAF the lesion site is peripheral and postganglionic. We evaluated the SkVR in response to various stimuli in MSA and PAF, to determine differences in skin vasomotor involvement between these two patient groups.

METHODS

25 subjects (10 MSA, 7 PAF, 8 healthy controls) were studied. Baseline recordings of skin blood flow were obtained with a laser Doppler probe on the left index finger pulp and forearm. The subject then underwent a variety of stimuli with rest periods in between to reestablish baseline SkBF. These stimuli were: single deep inspiration (inspiratory gasp); mental arithmetic; bilateral leg elevation and cutaneous cold.

RESULTS

Healthy control subjects demonstrated marked SkVRs on the finger pulp to each of the stimuli of a magnitude similar to those seen in previous studies, but no SkVRs on the forearm. In MSA SkVRs to inspiratory gasp on the finger pulp were reduced relative to controls. In PAF SkVRs were reduced relative to controls or MSA. The magnitude of SkVR response to gasp and cutaneous cold in PAF was significantly less than in healthy controls. In addition, the magnitude of the response in PAF was significantly less than in MSA for inspiratory gasp.

CONCLUSIONS

PAF showed a decreased SkVR response to all 4 stimuli, the response being significantly less than controls (for inspiratory gasp and cutaneous cold) or MSA (cutaneous cold inspiratory gasp). The decreased responses in PAF may reflect the extensive postganglionic sympathetic denervation seen in this group. The measurement of SkVR may therefore provide a non-invasive aid to the differentiation of MSA and PAF.

Mental strain in medical students during simulator training measured by forehead sweating

Forehead sweating developed in 78% of medical students when they attempted tracheal intubation on a simulator, and increased during subsequent attempts if the first attempt was not successful. Thus, forehead sweating may be a useful index of mental strain.

Ocular Amyloid Angiopathy Associated with Familial Amyloidotic Polyneuropathy Caused by Amyloidogenic Transthyretin Y114C

PURPOSE

To report the clinicopathological findings for a unique ocular amyloid angiopathy in patients with familial amyloidotic polyneuropathy (FAP) caused by amyloidogenic transthyretin Y114C.

DESIGN

Three case reports.

METHODS

Retrospective review of clinicopathological findings, course, and treatment of the 3 patients.

MAIN OUTCOME MEASURES

Visual acuity, intraocular pressure, fundus photography, fluorescein angiography (FA), indocyanine green angiography, and histopathological analysis.

RESULTS

In the 32-year-old patient, in the early stage of FAP, indocyanine green angiography demonstrated multiple sites of hyperfluorescence, with staining along major choroidal veins. Retinal vessels appeared normal clinically and on FA. In the 48-year-old patient, who had late-stage FAP, examination of the fundus revealed pinpoint white amyloid opacities over the retinal surface, sheathing of retinal vessels, and scattered retinal hemorrhages. Fluorescein angiography showed vascular closure, focal staining, and microaneurysms. Indocyanine green angiography revealed multiple sites of hyperfluorescence, with staining along retinal and choroidal vessels. Examination during follow-up revealed that these vascular changes continued to progress. Histopathological study of an eye obtained at autopsy from the 49-year-old patient revealed marked intravascular and extravascular amyloid deposition.

CONCLUSIONS

Severe and progressive amyloid angiopathy causing visual disturbance was seen in patients with FAP caused by amyloidogenic transthyretin Y114C.

Transthyretin synthesis in rabbit ciliary pigment epithelium

Ocular symptoms of transthyretin (TTR)-related familial amyloidotic polyneuropathy (FAP) suggest that ciliary pigment epithelium (CPE) may synthesize TTR and its TTR may lead to amyloid formation in addition to TTR from vessels and retinal pigment epithelium (RPE). To clarify sites of TTR synthesis in ocular tissues, we performed in situ hybridization and reverse transcription-polymerase chain reaction (RT-PCR) for qualitative detection of TTR mRNA. In addition, we quantified levels of TTR mRNA expression by means of real-time quantitative RT-PCR. Furthermore, although TTR is an anti-acute phase protein in serum level, no reports on changes in TTR expression in ocular tissues during acute inflammation exist. To investigate changes in TTR expression in ocular tissues during inflammation, we induced uveitis by endotoxin challenge in rabbits and used real-time quantitative RT-PCR to examine changes in TTR mRNA expression in ocular tissues. In situ hybridization and RT-PCR qualitatively demonstrated TTR mRNA not only in RPE but also in CPE. Real-time quantitative RT-PCR showed that the level of TTR mRNA expression in the CPE was about one-third of that in the RPE. TTR mRNA expression in ocular tissues decreased as the degree of inflammation increased. These results suggest that TTR synthesized in the CPE may lead to ocular manifestations, especially glaucoma, in FAP. TTR mRNA also acts as an anti-acute phase reactant in ocular tissues.

Measurement of skin vasoconstrictor response in healthy subjects

OBJECTIVES

Laser Doppler flowmetry enables non-invasive quantification of skin blood flow and its sympathetically mediated change. Four different maneuvers were performed in 60 healthy subjects aged 20-78 years to investigate their variability, reproducibility and to determine the influence of gender, age and height.

MATERIAL AND METHODS

Skin blood flow was measured on the pulp of both index fingers using laser Doppler flowmetry. Vasoconstriction was induced by deep inspiratory gasp, arm dependency, acoustic stimulation and a modified cold pressor test.

RESULTS

More than 95% of normal subjects showed a vasoconstrictor response to cold pressure test and 100% to inspiratory gasp. In all other maneuvers vasoconstrictor response was less reliable. The magnitude of vasoconstrictor responses decreased with age in all maneuvers, while latencies remained unchanged. Only during inspiratory gasp men showed more pronounced vasoconstrictor response compared with women. Body height influenced latencies if peripheral stimuli were applied like in the cold pressor and arm dependency tests.

CONCLUSIONS

Inspiratory gasp and the modified cold pressor test were found to be more suitable maneuvers for routine clinical testing than arm dependency and acoustic stimulation. Normal data also for side differences are provided as a base for routine clinical testing in systemic and unilateral neurological disorders.

Neurodegeneration in familial amyloid polyneuropathy: from pathology to molecular signaling

Familial amyloid polyneuropathy (FAP) is an autosomal dominant neurodegenerative disorder related to the systemic deposition of mutated transthyretin (TTR) amyloid fibrils, particularly in peripheral nervous system (PNS). TTR fibrils are diffusely distributed in the PNS of FAP patients, involving nerve trunks, plexuses and ganglia. In peripheral nerves, amyloid deposits are prominent in the endoneurium, near blood vessels, Schwann cells and collagen fibrils. Fiber degeneration is axonal, beginning in the unmyelinated and low diameter myelinated fibers. Several hypotheses have been raised to explain axonal and neuronal loss: (i) compression of the nervous tissue by amyloid; however, a cause-effect relationship between amyloid deposition, structural nerve changes and degeneration was never clearly made; (ii) role of nerve ischemia secondary to lesions caused by perivascular amyloid, which is also doubtful as compromised blood flow was never demonstrated; (iii) lesions in the dorsal root ganglia neurons or Schwann cells. Recently, evidence for the presence of toxic non-fibrillar TTR aggregates early in FAP nerves constituted a first step to unravel molecular signaling related to neurodegeneration in FAP. The toxic nature of TTR non-fibrillar aggregates, and not mature TTR fibrils, was evidenced by their ability to induce the expression of oxidative stress and inflammation-related molecules in neuronal cells, driving them into apoptotic pathways. How these TTR aggregates exert their effects is debatable; interaction with cellular receptors, namely, the receptor for advanced glycation endproducts (RAGE), is a probable candidate mechanism. The pathology and the yet unknown molecular signaling mechanisms responsible for neurodegeneration in FAP are discussed.

Hereditary transthyretin amyloidosis from a Scandinavian perspective

Hereditary transthyretin (TTR) amyloidosis is a rare often fatal form of systemic amyloidosis, that until recently was considered intractable, with the patients dying from the disease 5-15 years after onset. The phenotype of the disease varies according to the type of mutation, but generally the heart and/or the nervous system is affected. Liver and in some cases heart transplantation has now been shown to stop the progress of the disease, but the outcome depends on the patients' status at the time of operation, as no substantial improvement of the patients' symptoms has been noted after the procedure. Thus an early diagnosis is of importance for the outcome. In the following, we summarize our knowledge of the amyloidogenic TTR mutations found in the Scandinavian countries, their symptoms, how to settle the diagnosis and the outcome of transplantation. Besides, the problems arising from our capability to genetically test asymptomatic members of affected families for the trait will be discussed.

Reflex responses to insertion of the intubating laryngeal mask airway, intubation and removal of the ILMA

We studied 21 patients (ASA 1 or 2) to investigate the skin vasomotor reflex (SVmR) and haemodynamic responses to insertion of an intubating laryngeal mask airway (ILMA), tracheal intubation using the ILMA and removal of the ILMA. Anaesthesia was induced with fentanyl, midazolam, vecuronium and nitrous oxide. A size 4 ILMA was inserted using the standard technique, and a silicone reinforced tracheal tube (7.5 mm, ID) was passed through it. After confirming successful intubation, the ILMA was removed using the stabilizing rod. The three procedures were performed at approximately one-minute intervals. Insertion of the ILMA, intubation and removal of the ILMA all significantly reduced the skin blood flow on the ring finger in all patients. The mean amplitudes of the SVmR were 0.46 (SD 0.29), 0.54 (0.32) and 0.68 (0.21) respectively. The magnitude of the SVmR and the haemodynamic changes induced by removal of the ILMA were significantly larger than those accompanying the other two procedures. Use of the ILMA for intubation and removal of the ILMA produces three stimuli and the removal of the ILMA produces the greatest response.

Amyloid deposition in ocular tissues of patients with familial amyloidotic polyneuropathy (FAP)

It is known that the severity of ocular symptoms does not always correlate with the systemic symptoms in patients with familial amyloidotic polyneuropathy (FAP ATTR V30M). The ocular tissues may have their own TTR metabolic system. The aim of this study is to clarify the distribution of amyloid deposition in the ocular tissues and to investigate the relationship between ocular symptoms and histopathological changes. We analyzed histopathologically 9 autopsied eyes taken from 3 Japanese and 6 Swedish patients with FAP ATTR V30M. Localization of amyloid deposition varied among the different cases, but there were some tendencies in the distribution. The degree of amyloid deposition in the ocular tissues was not always correlated with the duration of the disease. The frequency of amyloid deposition in the conjunctiva, iris, trabecular meshwork and vitreous body were 88.9%, 44.4%, 11.1% and 11.1% respectively in the 9 patients. These frequencies in the histopathological changes correlated with the frequencies in the clinical ocular manifestations as previously reported.

Early liver transplantation is essential for familial amyloidotic polyneuropathy patients' quality of life

Nineteen patients, who had undergone liver transplantation for familial amyloidotic polyneuropathy, had answered a quality of life questionnaire including 61 questions on somatic and mental symptoms, social aspects of life, confidence and satisfaction before, one year, and two years after transplantation. We found that patient satisfaction was generally good two years or more after the transplantation. Most of the patients were very or quite satisfied with the result. All of them had the drive to go on and felt hopeful about the future. However, on the second follow-up, 37% of the patients noted that they felt more insecure in their everyday life and there was a significant difference between the two assessments. The diarrhea score became worse between one and two years after the transplantation and was closely related to the duration of the gastrointestinal symptoms and to the duration of the disease before transplantation. The mental symptoms also increased significantly between the evaluations and this related to the severity of the somatic symptoms. Our conclusion is that liver transplantation should be performed before advanced somatic symptoms start to develop in order to improve the patients' chances of a good quality of life following liver transplantation.

Autonomic nervous function assessment using thermal reactivity of microcirculation

There are only a few reliable objective methods of diagnosing peripheral neuronal damage suitable for routine use; the most important is based on measurement of nerve conduction velocity, which only shows changes when severe disturbances are already present. However, it is precisely at this stage that the possibilities of therapy are no longer satisfactory. As small fibres are affected earlier in the course of most forms of PNP than the large ones, assessment of afferent as well as efferent C-fibre function gains importance in the management of this widespread disease. In assessment of autonomic dysfunction, variability of the heartbeat with deep breathing or the Valsalva manoeuvre is a good and generally accepted test, although not strongly associated with other PNP test abnormalities. However, axonal degeneration starts in the most distal parts of the axon due to impaired axonal transport. Therefore, the longest C-fibres, i.e. in the lower extremities, are affected first, and incipient changes are most prominent there. For this reason HLDF, a reflex response of the skin blood flow stimulated by heat, has advantages in assessment of early C-fibre dysfunction. Considering the fact that the afferent and efferent sympathetic C-fibres are involved in regulation of microcirculation, the skin blood flow regulation is investigated by means of laser Doppler flowmetry. The microcirculation is stimulated by heat and the reaction of microcirculation is assessed as a value for the function of afferent and efferent (sympathetic) C-fibres. The results of this method are in close correlation with electrophysiologic tests, which is not achieved with sudomotor function.

Endothelium-dependent vasodilatation in patients with familial amyloidotic polyneuropathy

We examined endothelium-dependent vasodilatation in 15 familial amyloidotic polyneuropathy (FAP) amyloidogenic transthyretin (ATTR) Valine30Methionine (Val30Met) patients and 12 healthy volunteers. Using ultrasonography, we measured the radial artery diameters under both baseline and hyperemic conditions. Endothelium-dependent vasodilatation was expressed as a percent increase in the diameters of the radial artery after induced hyperemia. Endothelium-dependent vasodilatation tended to decrease in the patients, compared with healthy volunteers. Responses were not elicited at all in patients with disease of more than 9 years' duration. Linear negative correlation was observed between endothelium-dependent vasodilatation and disease duration (P < 0.01). Correlation between endothelium-dependent vasodilatation and degree of autonomic dysfunction was significant (P = 0.0524) and for age was close to significance (P = 0.051). These results suggest that the peripheral vasomotor dysfunction in FAP patients may predominantly depend on the amount of amyloid deposition around the vessels through the course of illness.

Japanese monozygotic twins with familial amyloidotic polyneuropathy (FAP) (ATTR Val30Met)

Twenty-nine-year-old twin brothers having the amyloidogenic transthyretin (ATTR) Val30Met gene developed the clinical symptoms of familial amyloidotic polyneuropathy (FAP) in 1995. The twins had the same educational background and lived in the same district. FAP manifestations were similar in both cases, although electromyographic examinations revealed sensorimotor polyneuropathy in No. 1 and sensory polyneuropathy in No. 2. DNA analysis revealed that they were monozygotic twins. In addition to environmental factors, genetic factors may play an important role in determining the onset of FAP.

Effect of sildenafil citrate (Viagra) on erectile dysfunction in a patient with familial amyloidotic polyneuropathy ATTR Val30Met

A 34-year-old male patient with familial amyloidotic polyneuropathy (FAP) amyloidogenic transthyretin (ATTR) Valine30Methionine (Val30Met), who underwent a liver transplantation in Sweden in 1994, was treated with sildenafil citrate (Viagra) to ameliorate his erectile dysfunction (ED). Some clinical symptoms and the examination data for autonomic functions were improved after liver transplantation, but ED was never improved after the operation. Five years after liver transplantation, he requested a sildenafil citrate therapy to enhance his erectile potential. One and a half hours after the administration of 25 mg of sildenafil citrate, the skin surface temperature around the pelvic area increased and the penis became erect, though the postdose hemodynamic parameters did not significantly change from the respective baseline or predose values. He was able to have sexual intercourse, though ejaculation did not occur. This case report appears to suggest that sildenafil citrate is an effective drug to treat ED in patients with an organic impairment of the autonomic nervous system without altering systemic circulation.

Advanced glycation end product in familial amyloidotic polyneuropathy (FAP)

OBJECTIVES

Advanced glycation end products (AGE) are present in amyloid deposits in beta2-microglobulin amyloidosis, and it has been postulated that glycation of beta2-microglobulin may be involved in fibril formation. The aim of this paper was to ascertain whether AGE occur in amyloid deposits in familial amyloidotic polyneuropathy (FAP).

SETTING

Department of Medicine, Umeå University Hospital and First Department of Internal Medicine, Kumamoto University School of Medicine.

DESIGN

The presence of AGE was sought immunohistochemically and biochemically in amyloid-rich tissues from patients with FAP.

SUBJECTS

Biopsy specimens from nine patients and 10 controls were used for the immunohistochemical analysis. For amyloid preparation, vitreous samples from three FAP patients were used.

RESULTS

Immunohistochemical studies using a polyclonal anti-AGE antibody revealed positive immunoreactivity in intestinal materials, but the pattern of reactivity was unevenly distributed; it was often present in the border of amyloid deposits, or surrounding them. Non-amyloid associated immunoreactivity was also observed in a few regions of the specimens, although the AGE-positive structures were situated in areas containing amyloid deposits. Western blotting of purified amyloid from the vitreous body of FAP patients revealed a significant association of AGE with amyloid fibrils.

CONCLUSION

The immunoreactivity for the AGE antibody suggests that AGE may be involved in fibril formation in FAP.

Late-onset familial amyloid polyneuropathy type I (transthyretin Met30-associated familial amyloid polyneuropathy) unrelated to endemic focus in Japan. Clinicopathological and genetic features

Clinicopathological and genetic features were assessed on 35 Japanese families affected by late-onset familial amyloid polyneuropathy type I (transthyretin Met30-associated familial amyloid polyneuropathy, FAP TTR Met30) whose siblings were unrelated to endemic Japanese foci. In these patients (50 years or older), the most common initial symptom was paraesthesias in the legs. Autonomic symptoms were generally mild and did not seriously affect daily activities. The male-to-female ratio was extremely high (10.7 : 1). A family history was evident in only 11 out of 35 families, and other patients were apparently sporadic. The rate of penetrance was very low. Symptomatic siblings of familial cases showed a late age of onset, male preponderance and clinical features similar to those of the probands. Asymptomatic carriers, predominantly female, were detected relatively late in life. The geographical distribution of these late-onset, FAP TTR Met30 cases was scattered throughout Japan. In three autopsy cases and 20 sural nerve biopsy specimens, neurons in sympathetic and sensory ganglia were relatively preserved. Amyloid deposition was seen in the peripheral nervous system, particularly in the sympathetic ganglia, dorsal root ganglia and proximal nerve trunks such as sciatic nerve. These abnormalities were milder than those seen in typical early-onset FAP TTR Met30, as observed in two Japanese endemic foci of this disease. While axonal degeneration was prominent in myelinated fibres, resulting in severe fibre loss, unmyelinated fibres were relatively preserved. Our cases of late-onset FAP TTR Met30 showed features distinct from those of typical early-onset FAP TTR Met30 that occurred in the two Japanese endemic foci. Factors responsible for clinicopathological differences between these two forms of FAP TTR Met30 need to be identified.

Gastrointestinal dysfunction in familial amyloidotic polyneuropathy (ATTR Val30Met)--comparison of Swedish and Japanese patients

The aim of the present study was to compare the clinical symptoms of Swedish and Japanese patients with familial amyloidotic polyneuropathy (ATTR Val30Met), especially gastrointestinal disturbances, and to correlate the findings with survival. Seventy-three Swedish and 47 Japanese patients were available for the study. Thirty-two Swedish and 7 Japanese patients had undergone liver transplantation. The mean age at onset was 50 for Swedish and 35 for Japanese patients (P < 0.001; non-transplanted patients). Fifty-five percent of Japanese patients had gastrointestinal disturbances from onset, compared to 22% of Swedish patients (P < 0.05; whole population). The Swedish patients average survival after the onset was significantly longer than Japanese patients (P < 0.05; non-transplanted patients). An early onset of gastrointestinal symptoms was correlated to a decreased survival for Swedish, but not for Japanese patients. Age at onset was not correlated to survival neither for Swedish nor for Japanese patients. We conclude that the clinical expressions of familial amyloidotic polyneuropathy ATTR Val30Met are different in Swedish and Japanese patients. The survival after the onset was shorter for Japanese patients, who also had an earlier onset of gastrointestinal disturbances, especially diarrhea than Swedish patients.

Familial Amyloidotic Polyneuropathy: domino liver transplantation

BACKGROUND/AIMS

The primary cause of Familial Amyloidotic Polyneuropathy is a variant transthyretin gene on chromosome 18. Progressive polyneuropathy followed by fatal cardiac and renal failure commonly manifest during middle age. Within 10 years after onset of clinical symptoms, affected individuals usually die due to malnutrition or heart failure. Currently, liver transplantation is the only available therapeutic option.

METHODS

We performed liver transplantation in two patients with Familial Amyloidotic Polyneuropathy carrying the transthyretin-30 mutant. Two patients aged more than 50 years received the two explanted amyloidotic livers. This procedure is called Domino liver transplantation. We report the outcome in the studied subjects and analyze the metabolic consequences of this procedure.

RESULTS

We determined the serum half-life of transthyretin-30 as 2.25 days using daily monitoring of transthyretin-30 levels. An affected amyloidotic patient had an increased serum concentration of lipoprotein(a) of 78 mg/dl before transplantation. The tumor patient, who received the organ from this affected patient, developed an almost identical serum concentration of lipoprotein(a) after liver transplantation, confirming the liver as the primary site of synthesis of this lipoprotein.

CONCLUSION

Once Domino liver transplantation has been performed, the impact of the liver-dependent metabolism of specific proteins of interest can be studied.

Investigation into thiol conjugation of transthyretin in hereditary transthyretin amyloidosis

BACKGROUND

For all forms of amyloidosis, the amyloid-generating mechanism is unknown. Familial amyloidotic polyneuropathy type I is caused by a variant transthyretin (TTR Met-30). As electrospray ionization mass spectrometry (ESI-MS) discloses both thiol-conjugated and -unconjugated forms of wild-type and variant TTR, we wanted to investigate the relationship between TTR conjugation and clinically overt amyloid disease.

METHODS

Plasma from 35 individuals (12 symptomatic TTR Met-30 carriers, nine asymptomatic and 14 healthy control subjects) were analysed using ESI-MS.

RESULTS

The total TTR concentration was significantly lower in symptomatic TTR Met-30 carriers than in control subjects. An increased percentage of conjugated TTR Met-30 was found in symptomatic carriers compared with asymptomatic, whereas the percentage conjugated wild-type TTR was similar for control subjects, asymptomatic and symptomatic TTR Met-30 carriers.

CONCLUSION

The finding of a decreased ratio of unconjugated to conjugated TTR Met-30 in plasma samples from symptomatic TTR Met-30 carriers indicates that thiol conjugation of TTR could be involved in amyloid formation.

Magnitude of skin vasomotor reflex represents the intensity of nociception under general anesthesia

Because nociceptive stimuli induce the skin vasomotor reflex (SVmR), the assessment of the SVmR would be a useful indicator to represent nociception. We examined 39 adult patients for the relationship between the magnitude of the SVmR and the intensity of nociceptive stimulus that induced the SVmR. Under oxygen-nitrous oxide (50%) and sevoflurane anesthesia, the SVmR was induced by an electrical impulse to the ulnar nerve and detected by a laser Doppler flowmeter. Study 1: under the end-tidal concentrations of sevoflurane at 1.2% (n = 10), 1.7% (n = 9) or 2.2% (n = 10), the SVmR was tested by a 2-s, 50-Hz tetanic electrical impulse with a current intensity changing (40, 50 or 60 mA) in a randomized order. Study 2: under the end-tidal concentration of sevoflurane at 1.7% (n = 10), the SVmR testing was performed with a 50-mA, 50-Hz tetanic electrical impulse with the current duration changing (2, 3 or 4 s) in a randomized order. The studies demonstrated significant correlations of (1) the current intensity which induces the skin vasomotor reflex (SVmR) vs. the magnitude of the SVmR under the three different anesthesia depths, (2) the anesthesia depth vs. the magnitude of the SVmR (inverse proportion) under the same current intensity and (3) the duration of electrostimulation vs. the magnitude of the SVmR. Thus, the SVmR could be helpful for the objective assessment of nociception and anti-nociceptive effects in individual cases.

Assessing the level of regional blockade under general anesthesia using the skin vasomotor reflex test

We investigated whether skin vasomotor reflex (SVmR) testing can be used to assess the sensory blockade level under light general anesthesia. In 15 patients scheduled for abdominal gynecological surgery, the SVmR was tested under inhaled isoflurane or sevoflurane (0.5%-0.6%) with nitrous oxide (50%). Seven minutes after the epidural injection (5-10 mL of 2% lidocaine), a tetanic electrical stimulus (20 mA, 2 s) was applied to the skin and repeated sequentially from the L3 dermatome in the cephalad direction. Changes in the laser Doppler skin blood flow on the index finger tip were assessed for the SVmR. If there was a positive response, SVmR testing was discontinued. The relationship between the uppermost dermatome of the negative SVmR response and the intraoperative effectiveness of the epidural block was determined. In 11 patients, we confirmed a clear boundary of skin dermatome by the SVmR test. The uppermost dermatome of the negative SVmR response at higher than the T7 level was necessary to maintain the combined epidural and light general anesthesia for the transabdominal gynecological surgery (P = 0.002). We conclude that SVmR testing is useful in estimating the blockade level of regional anesthesia under light general anesthesia.

IMPLICATIONS

Considering "preemptive analgesia," a complete sensory blockade should be established before a skin incision. In 11 of 15 patients under epidural/ general anesthesia, we confirmed a clear dermatome boundary using the skin vasomotor reflex test. This test could be an indicator for estimating the sensory blockade level of patients under general anesthesia.

Visceral orthostatic hypotension in patients with severe autonomic dysfunction

Although changes in the blood flow of the cerebral vessels and the peripheral vessels in the extremities after changing body postures have been well examined in patients with orthostatic hypotension (OH), such changes in visceral vessels have not been well investigated. To elucidate the effect of autonomic dysfunctions on changes in the abdominal blood flow, the blood flow velocity of the portal vein was measured by Doppler ultrasonography in 11 patients with familial amyloidotic polyneuropathy (FAP) (Met30), 3 with pandysautonomia, 1 with Shy-Drager syndrome, and 10 healthy controls, in the supine and at the upright position. Among the 15 patients with the above-mentioned autonomic disorders, 5 of the patients showed a marked decrease in blood flow after standing, and one of these 5 patients exhibited transient hepatic and intestinal ischemia during intensive rehabilitation because of a severe decrease in visceral blood flow. Another 7 patients exhibited moderate decreases in the blood flow after standing. In contrast, no such change was observed in the 10 healthy controls. The FAP patients with L-threo-3,4-dihydroxyphenylserine (L-threo-DOPS) administration showed no significant correlation between the degree of OH and the decrease in the blood flow of the portal vein, and the patients without the drug exhibited a weak correlation. On the contrary, the pandysautonomia and Shy-Drager syndrome patients exhibited a linear positive correlation. These results suggest that FAP is a disease for which this kind of ultrasonographic examination should be applied, and that Doppler ultrasonography may be a helpful tool to evaluate visceral OH.

Endoscopic and pathological manifestations of the gastrointestinal tract in familial amyloidotic polyneuropathy type I (Met30)

OBJECTIVES

To evaluate the characteristic changes in the gastrointestinal tract in familial amyloidotic polyneuropathy (FAP) (Met30), both fibre gastroscopy and colonoscopy studies were performed in FAP (Met30) patients. Microscopic changes were also examined in autopsied and biopsied materials from patients with FAP, and compared with data from autopsied samples from patients with AL amyloidosis, and secondary amyloidosis patients.

DESIGN

Endoscopic and histopathological study.

SETTING

Kumamoto University Hospital, Kumamoto, Japan.

SUBJECTS

Nine patients with FAP (Met30) underwent fibre gastroscopy and colonoscopy. Six autopsied and 23 biopsied gastrointestinal samples from FAP patients, four from autopsied amyloidosis (including two myeloma associated form), and two from autopsied secondary amyloidosis patients were examined for histopathological study.

MAIN OUTCOME MEASURES

Fibre gastroscopy and colonoscopy were employed for macroscopic study. Congo red and H-E staining were performed for histopathological study. Macroscopic changes in the gastrointestinal tract and microscopic differences in the amyloid distribution pattern were compared between the different types of amyloidosis.

RESULTS

Fibre gastroscopy and colonoscopy for nine FAP patients revealed that four showed a fine granular appearance in the duodenum, three showed lack of lustre, and two showed mucosal friability in the gastrointestinal tract; however, no macroscopic abnormality was observed in four other FAP patients. Histopathological examination of tissue from FAP patients revealed that, although a small amount of amyloid was recognized in the submucosa perivascular layer, a significant amount of amyloid was seen in and around the nerves of the gastrointestinal tract, but very little in Auerbach's nerve plexus. In total, the amount of deposited amyloid in the tissues was small compared with that in other types of systemic amyloidosis, such as AL and secondary amyloidosis.

CONCLUSION

These results suggest that the major reason why FAP patients show such severe gastrointestinal symptoms, compared with other types of systemic amyloidosis, may be because of the deposition of a significant amount of amyloid in the nerves in the gastrointestinal tract.

Down regulation of a harmful variant protein by replacement of its normal protein

To compensate for the hypoprotein and hypoalbuminemia of familial amyloidotic polyneuropathy (FAP) patients, 800 ml of fresh frozen plasma (FFP) was intravenously administered and change in total and variant transthyretin (TTR) levels were measured in the plasma. After injection of FFP, total plasma TTR levels were elevated and variant TTR levels decreased from 24 to 48 h, accompanied by an elevation of plasma total protein, albumin levels and TTR levels. To elucidate the mechanism of this phenomenon, a large amount of purified normal TTR from normal human plasma was intravenously injected in mice and FAP patients. By intravenous injection of 3 mg of the purified TTR to C57Black6, the expression of TTR mRNA decreased from 6 to 24 h post injection, and gradually increased up to 48 h post injection. After injecting 400 mg of normal TTR in each of 3 FAP patients, total plasma TTR levels were elevated and variant TTR levels decreased significantly from 24 to 48 h. These results suggested that down regulation of the harmful protein by replacement of its normal form of the protein occurred by this method. This phenomenon should be applied as the basis for one of the useful methods for decreasing the harmful proteins in the circulation.

Ocular manifestations of familial amyloidotic polyneuropathy type I: long-term follow up

AIMS

To obtain precise information on ocular manifestations of familial amyloidotic polyneuropathy (FAP) type I, the incidence of five main ocular manifestations--abnormal conjunctival vessels (ACV), keratoconjunctivitis sicca (KCS), pupillary abnormality, vitreous opacity, and glaucoma, were compared through long term follow up.

METHODS

Ocular examinations were performed in 37 FAP type I patients (Met30) from once to 12 times over a period of 1 to 12 years and 7 months.

RESULTS

The following incidences were observed on initial examination of each patient with FAP: ACV in 75.5%, pupillary abnormalities in 43.2%, KCS in 40.5%, glaucoma in 5.4%, and vitreous opacity in 5.4%. All ocular manifestations increased with the progression of FAP, and the incidence of ACV reached 100% during follow up: this may be helpful in the diagnosis of FAP.

CONCLUSION

Since no precise statistical ocular study on FAP with long term follow up has been performed, this report may provide important information to help elucidate the mechanism of the amyloid distributing process in the amyloid targeted organs of FAP and to provide the natural course of ocular manifestations of FAP.

Oxidative stress is found in amyloid deposits in systemic amyloidosis

Oxidative stress in human amyloid deposits from patients with systemic amyloidosis, such as familial amyloidotic polyneuropathy (FAP), primary amyloidosis, and secondary amyloidosis, was examined immunohistochemically by means of an affinity purified anti-hydroxynonenal (HNE) antibody to HNE, a marker of lipid peroxidation. Furthermore, the levels of thiobarbituric acid reactive substances (TBARS), which is another marker of lipid peroxidation, and the levels of protein carbonyl, a maker of protein modifications by free radicals, were determined in FAP patients and healthy controls. Affinity purified anti-HNE antibody reacted with amyloid deposits in all types of amyloid tissues examined. Significantly higher levels of TBARS and protein carbonyl were found in amyloid rich tissues of FAP patients compared with those in the control subjects. These results verify that lipid peroxidation via free radical injury occurs in amyloid deposits in systemic amyloidosis. The protein modifying properties of free radicals increase the likelihood that they play an important role in the amyloid formation process.

Impact of autonomic neuropathy on circulatory instability during liver transplantation for familial amyloidotic polyneuropathy

BACKGROUND

Circulatory instability with severe hypotension frequently complicates liver transplantation in patients with familial amyloidotic polyneuropathy. Autonomic dysfunction is found early in the course of the disease by analysis of beat-to-beat heart rate variability (HRV). The aim of the present study was to investigate the impact of autonomic neuropathy on intraoperative circulatory instability during liver transplantation for familial amyloidotic polyneuropathy.

METHODS

Twenty-two patients were evaluated at the Department of Medicine, Umea University Hospital, by spectral analysis of HRV and later received liver transplants at Huddinge University Hospital. The low-and high-frequency bands obtained by spectral analysis of HRV in the supine and upright positions, respectively, were used as representative of sympathetic and parasympathetic activity. Circulatory instability during transplantation was defined as a fall in systolic arterial blood pressure below 70 mmHg for more than 5 min during the preanhepatic phase.

RESULTS

Both arrhythmia preventing spectral analysis of HRV and a sympathetic variability peak below 2.5 mHz2 were significantly more common among patients with intraoperative circulatory instability (P=0.03 and 0. 004, respectively). A diminished increase in pulse rate when tilting the patients from the supine to the upright position was also more pronounced among patients with circulatory instability (P<0.05).

CONCLUSIONS

The majority of patients who will develop circulatory instability with a pronounced fall in arterial blood pressure can be identified by Poincare plots of R-R intervals and spectral analysis of HRV. A low sympathetic peak or arrhythmia precluding spectral analysis of HRV is significantly related to operative circulatory instability.

Charcot knee arthropathy with articular amyloid deposition in familial amyloidotic polyneuropathy

An extremely rare case of familial amyloidotic polyneuropathy (FAP) complicated by neuroarthropathy (Charcot joint) in the left knee joint and by intra-articular deposits of amyloid was observed. FAP-specific variant transthyretin (TTR) was found in the synovial fluid and amyloid deposits were confirmed in the synovium, cartilage and bone by Congo red staining and immuno-staining.

Reflex sympathetic dystrophy: skin blood flow, sympathetic vasoconstrictor reflexes and pain before and after surgical sympathectomy

To examine the pathophysiological mechanisms of vascular disturbances and to assess the role of the sympathetic nervous system, 12 patients with reflex sympathetic dystrophy (RSD) of the hand were studied using laser Doppler flowmetry. Cutaneous blood flow, skin resistance and skin temperature were measured at the affected and contralateral hands. Sympathetic vasoconstrictor reflexes were induced bilaterally by deep inspiration. Four patients were treated with unilateral surgical sympathectomy and pain and vascular changes were documented in follow-up investigations. (1) After acclimatization in cold environment (< or = 18 degrees C) blood flow and skin temperature were considerably lower on the affected side in 10 patients. No additional vasoconstrictor reflexes could be elicited. (2) After acclimatization in warm environment (22-24 degrees C) blood flow and skin temperature demonstrated no side differences in all cases. Vasoconstrictor responses were the same on both sides. (3) After sympathectomy vasoconstrictor reflexes were absent. Skin resistance was considerably higher on the affected side. In the first 4 weeks the affected hand was warmer and blood flow was higher compared with the healthy side. Thereafter, skin temperature and perfusion slowly decreased and the affected hand turned from warm to cold. Very regular high amplitude vasomotion waves occurred unilaterally. There were no signs of reinnervation. Two patients had long-term pain relief. We conclude as follows. (1) Side differences in skin temperature and blood flow are no static descriptors in RSD. They are dynamic values depending critically on environmental temperature. Therefore, they have to be interpreted with care when defining reliable diagnostic criteria. (2) Vascular disturbances in RSD are not due to constant overactivity of sympathetic vasoconstrictor neurons. Changes in vascular sensitivity to cold temperature and circulating catecholamines may be responsible for vascular abnormalities. Alternatively, RSD may be associated with an abnormal (side different) reflex pattern of sympathetic vasoconstrictor neurons due to thermoregulatory and emotional stimuli generated in the central nervous system. (3) After sympathectomy, denervation supersensitivity of blood vessels and intense vasomotion may be associated with recurrence of pain in some patients.

Non-neurogenic periodic fluctuations in heart rate and vasomotion appearing in familial amyloid polyneuropathy (FAP) Type I (Met30)

In order to evaluate the function of the autonomic nervous system, power spectral analysis of heart rate fluctuation and waveform observation of cutaneous vasomotion were conducted in 3 patients with familial amyloid polyneuropathy Type 1 (FAP) (Met30) with autonomic disorders. In 2 FAP patients in the early stage, both high (HFC: 0.12-0.4 Hz) and low frequency components (LFC: 0.04-0.12 Hz) in the heart rate spectrum, and basic (BW) and reflex waves (RW) in the vasomotion were all markedly suppressed. However, in an FAP patient in the advanced stage, prominent spectral peaks were recognized in both the spectral bands of LFC and HFC. HFCs were neither correspondent with the respiratory frequency nor depressed by atropine, and BW was not affected by acute denervation using a local anesthetic. RW was absent irrespective of the denervation. These results suggest that the denervated heart and vascular smooth muscles might have newly acquired periodic fluctuations, although the physiological mechanism and meanings remain to be investigated.