Influence of Breastfeeding Factors on Polyamine Content in Human Milk.

The polyamine content of human breast milk, which is the first exogenous source of polyamines for the newborn, can be affected by several factors associated with the mother, the infant, or breastfeeding itself. The aim of this study was to evaluate the influence of different breastfeeding factors on the polyamines found in human milk. For this study, a cohort of 83 mothers was considered for up to 4 months, and a subgroup of 33 mothers were followed during the first six months of breastfeeding. Two breast milk samples were collected at each sampling point (foremilk and hindmilk) and the polyamine content was determined by UHPLC-FL. Polyamine levels varied considerably between the mothers and tended to decrease over time. Putrescine was the minor polyamine, whereas spermidine and spermine contents were very similar. The concentrations of the three polyamines were significantly higher in hindmilk than foremilk (p < 0.001). Spermidine and spermine levels decreased significantly through the lactation progress (p < 0.05). Finally, slightly higher levels of polyamines were observed in the milk of mothers providing partial, rather than full, breastfeeding, although the differences were not significant. The polyamine content in human milk was found to change during a single feed (foremilk versus hindmilk) and as lactation progressed, mainly in response to the specific circumstances of the newborn.

[Lambert-Eaton myasthenic syndrome]. / Síndrome miasteniforme de Lambert-Eaton.

INTRODUCTION: Early diagnosis based on clinical findings, neurophysiological studies and serum antibody titres allows early initiation of symptomatic treatment and oncological screening. Reports of patients with LEMS in Latin America are scarce. AIM: This article aims to describe the characteristics of patients with LEMS from a private centre in Buenos Aires, Argentina, and to compare them with those of other series that have been published. PATIENTS AND METHODS: The medical records of 13 patients with LEMS with clinical findings, compatible electromyogram and/or positive antibodies were reviewed. Follow-up was performed until associated neoplasia was ruled out or confirmed according to the recommended algorithms. RESULTS: Four patients were diagnosed with T-LEMS, two of them with small-cell lung carcinoma. Of the nine patients with NT-LEMS, five had a DELTA-P score of 3 and 4. Nine patients presented with the classic clinical triad from the onset of the disease. All patients had electromyogram findings compatible with presynaptic neuromuscular plaque defect. Of the total, 70% improved symptomatically with pyridostigmine. CONCLUSIONS: The clinical findings, together with compatible neurophysiological studies, are sufficient for the diagnosis of LEMS. The relationship between the DELTA-P score and the risk of small-cell lung carcinoma could not be replicated. Symptomatic treatment with pyridostigmine represents an effective therapeutic alternative.

TITLE: Síndrome miasteniforme de Lambert-Eaton.Introducción. El síndrome miasteniforme de Lambert-Eaton (LEMS) es una patología paraneoplásica (T-LEMS) o idiopática autoinmunitaria (NT-LEMS) ocasionada por autoanticuerpos contra los canales de calcio dependientes del voltaje presinápticos de la unión neuromuscular. El 60% de los T-LEMS se asocia a carcinoma de pulmón de células pequeñas. Una puntuación Dutch-English LEMS Tumor Association Prediction (DELTA-P) mayor de 3 denota un riesgo elevado de dicha asociación. El diagnóstico precoz fundado en los hallazgos clínicos, estudios neurofisiológicos y dosificación de títulos de anticuerpos en el suero permite iniciar tempranamente el tratamiento sintomático y la búsqueda oncológica. Son escasos los informes de pacientes con LEMS en Latinoamérica. Objetivo. Describir las características de pacientes con LEMS de un centro privado de Buenos Aires, Argentina, y compararlas con las de otras series publicadas. Pacientes y métodos. Se revisaron historias clínicas de 13 pacientes con LEMS con hallazgos clínicos, electromiograma compatible y/o anticuerpos positivos. Se realizó seguimiento hasta descartar o confirmar una neoplasia asociada de acuerdo con los algoritmos recomendados. Resultados. Cuatro pacientes presentaron diagnóstico de T-LEMS, dos de ellos con carcinoma de pulmón de células pequeñas. De los nueve pacientes con NT-LEMS, cinco presentaron una puntuación DELTA-P de 3 y 4. Nueve pacientes presentaron la tríada clínica clásica desde el inicio. Todos los pacientes presentaron en el electromiograma hallazgos compatibles con defecto de placa neuromuscular presináptico. El 70% mejoró sintomáticamente con piridostigmina. Conclusiones. Los hallazgos clínicos, junto con los estudios neurofisiológicos compatibles, resultan suficientes para el diagnóstico de LEMS. No pudo replicarse la relación entre puntuación DELTA-P y riesgo de carcinoma de pulmón de células pequeñas. El tratamiento sintomático con piridostigmina representa una alternativa terapéutica eficaz.

Vasculitic Peripheral Neuropathy, Differences Between Systemic and Non-Systemic Etiologies: A Case Series and Biopsy Report.

BACKGROUND: Vasculitic peripheral neuropathy (VPN) is caused by vessel inflammation leading to peripheral nerve injury of acute-to-subacute onset. When VPN occurs in the context of systemic disease it is classified as Systemic Vasculitic Neuropathy (SVN) and as Non-Systemic Vasculitic Neuropathy (NSVN) when restricted to the nerves. OBJECTIVE: This study aimed to compare the clinical characteristics, biopsy findings and disease outcome in patients with VPN. METHODS: Clinical records of adult patients with VPN diagnosed at our institution between June-2002 and June-2019 were retrospectively reviewed. Demographic characteristics, clinical manifestations, nerve conduction studies, nerve biopsies, treatment and clinical evolution were analyzed in all patients with at least 6 months follow-up. RESULTS: Twenty-five patients with VPN were included (SVN, n = 10; NSVN, n = 15). No significant differences in demographic or clinical features were found between groups. The median delay between symptom onset and nerve biopsy was significantly longer in NSVN patients (10 vs 5.5 months, p = 0.009). Erythrocyte sedimentation rate (ESR) values over 20 mm/h were significantly more common in SVN patients (100% vs. 60%, p = 0.024). Nerve biopsies showed active lesions more frequently in treatment-naive patients compared to those who had received at least 2 weeks of corticosteroids (92% vs 38%; p = 0.03), with a higher proportion of definite VPN cases (92 vs 46%; p = 0.04). CONCLUSIONS: Although the clinical manifestations are similar, ESR is an important tool to help distinguish between both conditions. Early nerve biopsy in untreated patients increases diagnostic accuracy, avoiding misdiagnosis.

Postural tachycardia syndrome in syringomyelia: response to fludrocortisone and beta-blockers.

Orthostatic intolerance is occasionally reported by patients with syringomyelia and is usually attributed to vestibular symptoms or neurogenic orthostatic hypotension. Postural tachycardia syndrome has not been previously described in syringomyelia. A patient with long-standing syringomyelia and a Chiari type I anomaly developed disabling "panic-like" attacks associated to orthostatic intolerance five years after posterior fossa decompression and shunting of the syrinx. A head-up tilt test showed an early phase of postural orthostatic tachycardia followed by progressive arterial hypotension and bradycardia as seen in neurally mediated syncope. A magnetic resonance imaging scan showed a collapsed syrinx from the 3rd cervical to the 12th thoracic vertebra without syringobulbia. Fludrocortisone and beta-blockers led to resolution of symptoms. Partial sympathetic denervation of the legs in syringomyelia might explain the occasional occurrence of postural tachycardia syndrome. Postural tachycardia syndrome may be included as a possible cause of orthostatic symptoms in syringomyelia patients.

[Multifocal motor neuropathy. Immediate response to intravenous immunoglobulin]. / Neuropatía motora multifocal. Respuesta inmediata a la inmunoglobulina endovenosa.

Multifocal motor neuropathy, a rare insidious immune-mediated disorder, features muscular weakness and atrophy, as well as areflexia, due to nerve conduction block and is often associated with the presence of anti-GM1 antibody. We report a patient with a nine-year history of progressive upper limb weakness, misdiagnosed as amyotrophic lateral sclerosis, who responded within hours to intravenous immunoglobulin treatment with full recovery of muscle strength. This case highlights the need to search for conduction block in patients with lower motor neuron involvement.

[Acute peripheral demyelinating polyneuropathy and acute renal failure after administration of FK506]. / Polineuropatía desmielinizante periférica aguda e insuficiencia renal aguda secundaria a la administración de FK 506.

FK 506 is a potent immunosuppressive agent in clinical use in solid organ transplantation since 1989. Approximately 5% of patients receiving FK 506 develop major central nervous system toxicity but peripheral nervous system involvement is very uncommon, and there are only 4 reported cases of demyelinating polyneuropathy in patients who received a liver transplant. We report a case of demyelinating polyneuropathy associated with the use of FK 506 in a renal transplant recipient.

Focal stiff-person syndrome.

Stiff-person syndrome (SPS) is a disorder of motor function characterized by rigidity of axial musculature and fluctuating painful spasms, which are often induced by startle or emotional stimuli. Neurophysiological studies have demonstrated the presence of continuous motor unit activity in muscle at rest, with abnormally enhanced extereoceptive reflexes. Although criteria for the diagnosis of SPS were proposed, several variants of this syndrome have been described before. In this communication, we report the case of a patient with a focal form of SPS. A 39-year-old woman developed progressive instability in her gait, spasms and stiffness restricted to both legs. The electromyographic examination showed continuous motor unit activity of the affected muscles at rest. Moreover, high anti-GAD antibodies titers were found in CSF and serum. Clinical symptoms, electrophysiological and immunological profiles suggest a focal form of SPS. Clinical and immunological findings indicate that SPS is a heterogeneous disease, suggesting the need to redefine its diagnostic criteria. Definition of the range of clinical expression and immunological profiles could be important for the clinical management of these patients.

[Acute bilateral sensorineural hearing loss caused by immuno-mediated inner ear disease]. / Sordera neurosensorial aguda bilateral por enfermedad del oído interno inmuno-mediada.

The audiovestibular system can be affected by an immunologic etiology. The immune-mediated inner ear disease (IMIED) is a syndrome that includes rapidly progressive sensorineural hearing loss, vertigo and tinnitus, which occurs as a primary disorder or complicates certain autoimmune systemic conditions. However, if treated promptly with immunosuppression, the audiological sequel of IMIED may be avoided. We present a 28 year old female patient, who after rhinitis and mioarthralgias developed a vestibular syndrome. A week later she experienced bilateral hearing loss that progressed to deafness in 72 hours. The examination revealed horizontal and torsional nystagmus, a disrupted vestibulo-ocular reflex and vertigo with the positional changes. Laboratory data were normal except for eritrosedimentation rate (75 mm/1 hour). The autoantibodies usually present in rheumatologic autoimmune systemic diseases were negative. The antibodies to the 68-kD antigen found in the inner ear were positive. The chest x-ray and sinus x-ray were normal. The head magnetic resonance imaging with gadolinium and ear computed tomography were normal. Cerebrospinal fluid studies showed normal findings. With the possible diagnosis of IMIED we started early treatment with corticosteroids, with improvement in auditory and vestibular function thereafter. We highlight the early recognition of IMIED as a differential diagnosis in patients with acute bilateral hearing loss, because prompt treatment with immunosuppression might have a positive effect on auditory function recovery.

Neuropatía motora multifocal. Respuesta inmediata a la inmunoglobulina endovenosa. / [Multifocal motor neuropathy. Immediate response to intravenous immunoglobulin]

Multifocal motor neuropathy, a rare insidious immune-mediated disorder, features muscular weakness and atrophy, as well as areflexia, due to nerve conduction block and is often associated with the presence of anti-GM1 antibody. We report a patient with a nine-year history of progressive upper limb weakness, misdiagnosed as amyotrophic lateral sclerosis, who responded within hours to intravenous immunoglobulin treatment with full recovery of muscle strength. This case highlights the need to search for conduction block in patients with lower motor neuron involvement.

Polineuropatía desmielinizante periférica aguda e insuficiencia renal aguda secundaria a la administración de FK 506. / [Acute peripheral demyelinating polyneuropathy and acute renal failure after administration of FK506]

FK 506 is a potent immunosuppressive agent in clinical use in solid organ transplantation since 1989. Approximately 5

of patients receiving FK 506 develop major central nervous system toxicity but peripheral nervous system involvement is very uncommon, and there are only 4 reported cases of demyelinating polyneuropathy in patients who received a liver transplant. We report a case of demyelinating polyneuropathy associated with the use of FK 506 in a renal transplant recipient.

Sordera neurosensorial aguda bilateral por enfermedad del oído interno inmuno-mediada. / [Acute bilateral sensorineural hearing loss caused by immuno-mediated inner ear disease]

The audiovestibular system can be affected by an immunologic etiology. The immune-mediated inner ear disease (IMIED) is a syndrome that includes rapidly progressive sensorineural hearing loss, vertigo and tinnitus, which occurs as a primary disorder or complicates certain autoimmune systemic conditions. However, if treated promptly with immunosuppression, the audiological sequel of IMIED may be avoided. We present a 28 year old female patient, who after rhinitis and mioarthralgias developed a vestibular syndrome. A week later she experienced bilateral hearing loss that progressed to deafness in 72 hours. The examination revealed horizontal and torsional nystagmus, a disrupted vestibulo-ocular reflex and vertigo with the positional changes. Laboratory data were normal except for eritrosedimentation rate (75 mm/1 hour). The autoantibodies usually present in rheumatologic autoimmune systemic diseases were negative. The antibodies to the 68-kD antigen found in the inner ear were positive. The chest x-ray and sinus x-ray were normal. The head magnetic resonance imaging with gadolinium and ear computed tomography were normal. Cerebrospinal fluid studies showed normal findings. With the possible diagnosis of IMIED we started early treatment with corticosteroids, with improvement in auditory and vestibular function thereafter. We highlight the early recognition of IMIED as a differential diagnosis in patients with acute bilateral hearing loss, because prompt treatment with immunosuppression might have a positive effect on auditory function recovery.

[Chronic hereditary ataxic polyneuropathy]. / Polineuropatia atáxica hereditaria crónica.

Sensory ataxic polyneuropathies are characterised by the presence of sensory ataxia due to damage to large myelinated sensory fibres, with total or relative preservation of muscle strength, pain and temperature sensation. Hereditary ataxic polyneuropathies are exceptional and very few families with this disorder have been reported so far. We here describe the neurological, electrophysiological and sural nerve biopsy data of four siblings with an ataxic chronic polyneuropathy, starting after age 50. They had an ataxic gait which worsened in darkness, horizontal nystagmus, hypo or areflexia, and severe impairment of limbs' propriocaption. Nerve conduction studies showed absent sensory nerve action potentials in all nerves tested. Somatosensory evoked potentials showed reduced amplitude and prolonged latencies. Sural nerve biopsy showed a severe loss of myelinated and unmyelinated fibres. Symptoms slowly progressed over the years. The recognition of this syndrome is important in the search for the etiology of chronic ataxic neuropathies.

Disruption of spatial organization and interjoint coordination in Parkinson's disease, progressive supranuclear palsy, and multiple system atrophy.

Patients with basal ganglia diseases may exhibit ideomotor apraxia. To define the nature of the impairment of the action production system, we studied a repetitive gesture of slicing bread by three-dimensional computergraphic analysis in eight nondemented patients with Parkinson's disease in the "on" state, five with progressive supranuclear palsy and four with multiple system atrophy. Two patients with Parkinson's disease and two with progressive supranuclear palsy showed ideomotor apraxia for transitive movements on standard testing. A Selspott II system was used for kinematic analysis of wrist trajectories and angular motions of the shoulder and elbow joints. Patients with Parkinson's disease, progressive supranuclear palsy, and even some with multiple system atrophy exhibited kinematic deficits in the spatial precision of movement and velocity-curvature relationships; in addition, they failed to maintain proper angle/angle relationships and to apportion their relative joint amplitudes normally. Spatial disruption of wrist trajectories was more severe in patients with ideomotor apraxia. We posit that the basal ganglia are part of the parallel parieto-frontal circuits devoted to sensorimotor integration for object-oriented behavior. The severity and characteristics of spatial abnormalities of a transitive movement would therefore depend on the location and distribution of the pathologic process within these circuits.

[Neurological complications of renal transplant]. / Complicaciones neurológicas del trasplante renal.

Advances in surgical procedures and new immunosuppressor therapies have improved the outcome of renal grafts. However, these changes have been accompanied by infectious, neoplastic and neurologic complications. The purpose of this study was to determine the incidence of neurologic complications among 542 patients receiving a renal transplant (from living or cadaveric donors) at CEMIC between 1970 and 1996. Neurologic complications occurred in 43 patients (8%) as follows: 8 meningitis (1.5%), 8 acute confusional syndrome (1.5%), 7 encephalitis (1.3%), 7 cerebrovascular accidents (1.3%), 6 convulsions (1.1%), 3 tumors (0.5%), 3 femoral nerve lesion (0.5%), and 1 epidural lipomatosis (0.1%). Etiologic agents most commonly observed in meningitis were: Cryptococcus neoformans, Listeria monocytogenes and Mycobacterium tuberculosis. Major difficulties arose in the diagnosis of encephalitis. Diagnosis of the above complications required clinical astuteness and repeated bacteriologic, serologic and imaging studies.

Periodic limb movements in syringomyelia and syringobulbia.

Twenty-six patients with syringomyelia were studied with polysomnography to determine the frequency of periodic limb movements (PLM) and its relationship to the presence of a Chiari anomaly, the severity of corticospinal tract involvement, and localization of the syrinx. Sixteen patients showed PLM in stages I and II of non-REM sleep and three PLM also while awake. There were no statistically significant differences in overall disability, corticospinal signs, presence of an associated Chiari anomaly, and disease duration between patients with and without PLM, although there was a trend for patients with PLM to have more severe disease. There was preservation of the lumbosacral enlargement of the spinal cord by the syrinx in all patients with PLM. The latency delay between lower and upper limb muscles was suggestive of conduction along propriospinal pathways. Syringomyelia may lead to an abnormal state of spinal hyperexcitability favoring the appearance of PLM. Detailed magnetic resonance image studies of patients with different localizations of the syrinx cavities may help to determine which tracts are involved in the production of PLM.

Complicaciones neurológicas del trasplante renal. / [Neurological complications of renal transplant]

Advances in surgical procedures and new immunosuppressor therapies have improved the outcome of renal grafts. However, these changes have been accompanied by infectious, neoplastic and neurologic complications. The purpose of this study was to determine the incidence of neurologic complications among 542 patients receiving a renal transplant (from living or cadaveric donors) at CEMIC between 1970 and 1996. Neurologic complications occurred in 43 patients (8

) as follows: 8 meningitis (1.5

), 8 acute confusional syndrome (1.5

), 7 encephalitis (1.3

), 7 cerebrovascular accidents (1.3

), 6 convulsions (1.1

), 3 tumors (0.5

), 3 femoral nerve lesion (0.5

), and 1 epidural lipomatosis (0.1

). Etiologic agents most commonly observed in meningitis were: Cryptococcus neoformans, Listeria monocytogenes and Mycobacterium tuberculosis. Major difficulties arose in the diagnosis of encephalitis. Diagnosis of the above complications required clinical astuteness and repeated bacteriologic, serologic and imaging studies.

Polineuropatia atáxica hereditaria crónica. / [Chronic hereditary ataxic polyneuropathy]

Sensory ataxic polyneuropathies are characterised by the presence of sensory ataxia due to damage to large myelinated sensory fibres, with total or relative preservation of muscle strength, pain and temperature sensation. Hereditary ataxic polyneuropathies are exceptional and very few families with this disorder have been reported so far. We here describe the neurological, electrophysiological and sural nerve biopsy data of four siblings with an ataxic chronic polyneuropathy, starting after age 50. They had an ataxic gait which worsened in darkness, horizontal nystagmus, hypo or areflexia, and severe impairment of limbs propriocaption. Nerve conduction studies showed absent sensory nerve action potentials in all nerves tested. Somatosensory evoked potentials showed reduced amplitude and prolonged latencies. Sural nerve biopsy showed a severe loss of myelinated and unmyelinated fibres. Symptoms slowly progressed over the years. The recognition of this syndrome is important in the search for the etiology of chronic ataxic neuropathies.

Electrodiagnostic findings in syringomyelia.

Electrodiagnostic abnormalities are well known to occur in syringomyelia although the findings are nonspecific. The objective of this work was to describe different types of spontaneous electromyographic (EMG) activity and reflex responses, which may be useful and more specific than conventional findings for the electrodiagnosis of syringomyelia. We studied 43 patients with syringomyelia by four-channel surface EMG and by recording the long-latency responses to distal stimulation of the median and tibial nerves. Continuous motor unit activity (CMUA) was found in 18 patients, synchronous motor unit potentials (SMUP) in 10, respiratory synkinesis (RS) in 5, and myokymic discharges in 4. Long-latency responses (LLR) with latencies ranging from 55 to 150 ms were found in 14 patients. Patients with syringomyelia thus show a wide variation of spontaneous EMG activity. An increase in excitability of spinal motor neurons is probably the basic underlying mechanism.