Correlation between anemia and clinical severity in subacute combined degeneration patients.

OBJECTIVES: Subacute combined degeneration (SCD) is a demyelinating disease commonly caused by vitamin B12 deficiency. Several studies have been reported SCD could be accompanied by anemia. However, the correlation between anemia and clinical severity of SCD patients is unclear. In this study, we aim to analyze the clinical characteristics of SCD concomitant with anemia, and investigate the effect of anemia in predicting the severity of SCD. METHODS: A total 42 patients were included in the study. Clinical, laboratory, radiological findings, and outcomes from the patients were analyzed. All patients were treated with vitamin B12 for no less than 6 months and a functional disability rating scale was used to evaluate severity of neurological impairment at the time of admission and 3 and 6 months after admission in our study. RESULTS: 85.7% patients had macrocytosis. Decreased serum vitamin B12 levels were found in 27 patients (64.3%). MRI showed long-segment abnormality on the spinal cord in 22 patients. No differences in rating score were found in patients grouped by sex, age, clinical course, serum vitamin B12, or MRI manifestations at the time of admission or at the follow-up visits. Negative correlation was seen between hemoglobin levels and the clinical severity scores on admission. CONCLUSION: Not all patients with SCD concomitant with anemia had decreased serum vitamin B12 level. The inverse correlation between hemoglobin level and clinical severity suggests the degree of anemia can help in evaluating the extent of neurologic impairment.

Of dots and levels: a case of partial subacute combined degeneration.

Subacute combined degeneration of the spinal cord is a typical clinical syndrome due to vitamin B12 deficiency, characterised by the involvement of the posterior column and corticospinal tracts. Occasionally, it may present with atypical features such as a sensory level and Lhermitte's sign, both traditionally considered to be a feature of compressive myelopathy. Spinal magnetic resonance imaging strongly augments the diagnosis by exhibiting changes in the posterior column in the form of a 'dot'. We describe such a patient who responded to therapy.

A retrospective study of 23 cases with subacute combined degeneration.

PURPOSE: To study retrospectively the diverse presentations, ancillary tests and neuroimaging in patients with subacute combined degeneration (SCD). METHODS: Twenty-three Chinese patients with SCD were included in this study. The clinical presentations and laboratory data including comprehensive metabolic panel, serum folic acid, vitamin B12 levels, gastroscopy and images of spinal cord on magnetic resonance imaging (MRI) were evaluated. Rating scales for localizations of lesions and functional disabilities were used to define the severity of neurological impairment. RESULTS: No difference was found between men and women in the age of disease onset. For most of the patients, sensory symptoms, oftentimes as initial symptoms, occurred earlier than motor symptoms. The signs of the disease were more obvious than the symptoms. Six patients had sensory deficit levels mimicking transverse myelopathy. Anemia was not always detected in our patients with SCD. Normal or even elevated serum levels of vitamin B12 were found in seven patients. Spinal cord lesions on MRI were observed in six patients and the clinical and neuroimaging findings were not necessarily consistent. CONCLUSIONS: The sensory symptoms occur earlier than the motor symptoms in SCD patients. SCD patients may have sensory deficit level. Normal or even elevated serum levels of vitamin B12 may occur in patients with SCD.

Prevalence of MR imaging abnormalities in vitamin B12 deficiency patients presenting with clinical features of subacute combined degeneration of the spinal cord.

BACKGROUND AND AIMS: Subacute combined degeneration (SACD) of the spinal cord, characterized by degeneration of lateral and posterior columns, is often found in vitamin B12 deficiency. Our aim was to look for sensitivity of imaging in depicting the spinal cord abnormality in vitamin B12 deficient patients and to find any correlation of vitamin B12 levels with clinical scores/severity at time of presentation. MATERIAL AND METHODS: A total 54 patients with biochemically proven vitamin B12 deficiency were included in the study. In all these patients MR study of cervico-dorsal spine was done. All the patients after initiation of appropriate treatment were followed up for a minimum of two months. RESULTS: MRI showed cord signal abnormality in only 8 patients out of 54 patients with low sensitivity of 14.8%. After appropriate therapy, complete resolution of cord signal abnormalities was observed in all these 8 patients, on follow-up MR imaging. Significant negative correlation (r=-0.503, p<0.000) was seen between the clinical severity scores and initial vitamin B12 levels. CONCLUSION: Conventional MRI may not be a useful tool for the diagnosis of SACD as it has very low sensitivity. Inverse correlation of Vitamin B12 levels with clinical scoring suggests that initial serum vitamin B12 levels may help in predicting the clinical severity.

Cobalamin deficiency: clinical picture and radiological findings.

Vitamin B12 deficiency causes a wide range of hematological, gastrointestinal, psychiatric and neurological disorders. Hematological presentation of cobalamin deficiency ranges from the incidental increase of mean corpuscular volume and neutrophil hypersegmentation to symptoms due to severe anemia, such as angor, dyspnea on exertion, fatigue or symptoms related to congestive heart failure, such as ankle edema, orthopnea and nocturia. Neuropsychiatric symptoms may precede hematologic signs and are represented by myelopathy, neuropathy, dementia and, less often, optic nerve atrophy. The spinal cord manifestation, subacute combined degeneration (SCD), is characterized by symmetric dysesthesia, disturbance of position sense and spastic paraparesis or tetraparesis. The most consistent MRI finding is a symmetrical abnormally increased T2 signal intensity confined to posterior or posterior and lateral columns in the cervical and thoracic spinal cord. Isolated peripheral neuropathy is less frequent, but likely overlooked. Vitamin B12 deficiency has been correlated negatively with cognitive functioning in healthy elderly subjects. Symptoms include slow mentation, memory impairment, attention deficits and dementia. Optic neuropathy occurs occasionally in adult patient. It is characterized by symmetric, painless and progressive visual loss. Parenteral replacement therapy should be started soon after the vitamin deficiency has been established.

Cobalamin as a regulator of serum and cerebrospinal fluid levels of normal prions.

We have previously demonstrated that the concentration of normal prion proteins (PrP(C)) is increased in the serum and cerebrospinal fluid (CSF) of rats deficient in vitamin B(12) (cobalamin, Cbl). In this study, we investigated whether similar increases also occur in the serum and CSF of patients deficient in Cbl (Cbl-D), and whether the increase in serum levels can be corrected by Cbl therapy. The study involved two sample populations. The first consisted of 45 patients (13 patients with pernicious anemia [PA], 19 with other forms of anemia, and 13 healthy controls); and the second, 68 patients (five with subacute combined degeneration [SCD], 18 with amyotrophic lateral sclerosis, 22 with multiple sclerosis [MS], and 23 neurological controls). Serum PrP(C) levels were measured using an enzyme-linked-immunosorbent-assay before as well as after Cbl therapy. The mean serum PrP(C) levels in patients with PA were significantly higher than those of the controls (p=0.0017) but normalized after Cbl therapy; there was no significant change in the patients with other forms of anemia. Mean CSF PrP(C) levels in the patients with SCD were significantly higher than in the neurological controls (p<0.03). The serum and CSF PrP(C) levels of patients with PA and those with SCD were correlated significantly with serum (p=0.004) and CSF (p=0.0018) Cbl levels. In patients with MS, CSF PrP(C) concentrations were significantly lower than those of the controls regardless of their CSF Cbl levels. We found a correlation between Cbl and PrP(C) levels in the serum and CSF of Cbl-D patients, which suggests that Cbl may regulate the PrP(C) levels in the serum and CSF in humans.

Sequential involvement of the nervous system in subacute combined degeneration.

PURPOSE: Subacute combined degeneration (SCD) involves progressive degeneration of the spinal cord, optic nerve, and peripheral nerves. Vitamin B12 (VB12) is a co-factor in myelin synthesis. Because each cell that constitutes the myelin component in the central nervous system and peripheral nervous system is different, it is improbable that these cells undergo simultaneous degeneration. However, the sequence of degeneration in SCD has not been established. MATERIALS AND METHODS: In this study, we analysed medical records and electrophysiological data of patients who showed neurological symptoms and whose serum VB12 levels were lower than 200 pg/mL. RESULTS: We enrolled 49 patients in this study. Their mean VB12 level was 68.3 pg/mL. Somatosensory evoked potential (SEP) study showed abnormal findings in 38 patients. Of the 40 patients who underwent visual evoked potential (VEP) study, 14 showed abnormal responses. Eighteen patients showed abnormal findings on a nerve conduction study (NCS). In this study, abnormal posterior tibial nerve SEPs only were seen in 16 patients, median nerve SEPs only were seen in 3 patients, abnormal VEPs only in two, and abnormal NCS responses in one patient. No patient complained of cognitive symptoms. CONCLUSION: In SCD, degeneration appears to progress in the following order: lower spinal cord, cervical spinal cord, peripheral nerve/optic nerve, and finally, the brain.

Sequential Involvement of the Nervous System in Subacute Combined Degeneration

PURPOSE: Subacute combined degeneration (SCD) involves progressive degeneration of the spinal cord, optic nerve, and peripheral nerves. Vitamin B12 (VB12) is a co-factor in myelin synthesis. Because each cell that constitutes the myelin component in the central nervous system and peripheral nervous system is different, it is improbable that these cells undergo simultaneous degeneration. However, the sequence of degeneration in SCD has not been established. MATERIALS AND METHODS: In this study, we analysed medical records and electrophysiological data of patients who showed neurological symptoms and whose serum VB12 levels were lower than 200 pg/mL. RESULTS: We enrolled 49 patients in this study. Their mean VB12 level was 68.3 pg/mL. Somatosensory evoked potential (SEP) study showed abnormal findings in 38 patients. Of the 40 patients who underwent visual evoked potential (VEP) study, 14 showed abnormal responses. Eighteen patients showed abnormal findings on a nerve conduction study (NCS). In this study, abnormal posterior tibial nerve SEPs only were seen in 16 patients, median nerve SEPs only were seen in 3 patients, abnormal VEPs only in two, and abnormal NCS responses in one patient. No patient complained of cognitive symptoms. CONCLUSION: In SCD, degeneration appears to progress in the following order: lower spinal cord, cervical spinal cord, peripheral nerve/optic nerve, and finally, the brain.