Serum Cobalamin Concentrations Research Articles

Comparisons between cats with normal and increased fPLI concentrations in cats diagnosed with inflammatory bowel disease

The aim of this study was to compare age, serum albumin and cobalamin concentrations, serum alanine amino transferase and alkaline phosphatase activities, feline inflammatory bowel disease clinical disease activity index, pancreatic ultrasound findings, intestinal histopathology scores, outcome, treatment and clinical response between cats diagnosed with inflammatory bowel disease with normal or increased serum feline pancreatic lipase immunoreactivity concentrations. Medical records for 23 cats diagnosed with inflammatory bowel disease and with serum feline pancreatic lipase immunoreactivity concentrations available were reviewed. Three groups were compared; cats with serum feline pancreatic lipase immunoreactivity concentrations 2·0 to 6·8 µg/l (group A), 6·9 to 11·9 µg/l (group B) and ≥12·0 µg/l (group C). Sixteen of the 23 cats had increased serum feline pancreatic lipase immunoreactivity concentrations; 9 cats in group B and 7 cats in group C. The remaining seven cats were in group A. Cats with serum feline pancreatic lipase immunoreactivity concentrations ≥12·0 µg/l had significantly lower median serum albumin and cobalamin concentrations. No significant differences were identified between the three groups for age, serum alanine amino transferase and alkaline phosphatase activities, feline inflammatory bowel disease clinical disease activity index, pancreatic ultrasound findings, intestinal histopathology scores, clinical outcome, treatment or clinical response. Hypoalbuminaemia and hypocobalaminaemia were more frequently observed in cats with serum feline pancreatic lipase immunoreactivity concentrations ≥12·0 µg/l.

Serum autoimmune gastritis markers, pepsinogen I and parietal cell antibodies, in patients with Type 1 diabetes mellitus: A 5-year prospective study

To determine the temporal evolution of serum markers of autoimmune gastritis, mainly pepsinogen I (PI) and parietal cell antibodies (PCA), in patients with Type 1 diabetes mellitus (DM1). A 5-yr prospective follow-up study of 168 DM1 patients (87 men, aged 31 ± 9.3 yr) attending the endocrinology outpatient clinic of a university hospital evaluated in 2001 and 2006. Serum PI, gastrin, hemoglobin, cobalamin concentrations, PCA and antibodies to intrinsic factor were measured. In 2001, 11 patients had low PI concentrations and positive PCA (group I), 11 had only low PI concentrations (group II), and 33 had only positive PCA (group III). After 5 yr, PI remained low and PCA positive in all patients from group I. In group II, PI remained low in 4 and normalized in 7. In group III, 4 patients presented low PI concentrations after 5 yr, which remained normal in the other 29 subjects. PCA became negative in 17 patients from group III. In 2001, 3 of the 11 patients of group I had low cobalamin concentrations. In 2006, 2 additional patients from this group presented low cobalamin concentrations. These results show the importance of determining PI together with PCA, since the presence of abnormal results in both tests, that is low PI and positive PCA, is the association that best identifies patients with a higher risk to decrease cobalamin concentrations during follow-up.

Prevalence and prognostic impact of hypocobalaminemia in dogs with lymphoma

To determine the prevalence of hypocobalaminemia in dogs with multicentric lymphoma and to investigate any relationship between serum cobalamin concentration and disease outcome. Cohort study. 58 dogs with multicentric lymphoma. Serum cobalamin concentrations were measured in 58 dogs with multicentric lymphoma. Clinical signs, stage, and immunophenotype for dogs with hypocobalaminemia were compared with those for dogs with serum cobalamin concentrations above the lower end of the reference range. Survival times for dogs undergoing a cyclic multidrug chemotherapy protocol (n = 53) were similarly compared. Serum cobalamin concentrations for treated dogs that died or were euthanized before day 60 were compared with those of dogs still alive at day 60. Serum cobalamin concentrations ranged from < 150 to 1,813 ng/L, with a median concentration of 401 ng/L. Nine of the 58 (16%) dogs had hypocobalaminemia (serum cobalamin concentration < 252 ng/L). Three of 9 dogs with hypocobalaminemia survived to at least day 60, compared with 40 of 44 (91%) dogs without hypocobalaminemia (serum cobalamin concentration >or= 252 ng/L). Ten (10/53 [19%]) dogs undergoing a cyclic multidrug chemotherapy protocol died before day 60, and the median serum cobalamin concentration for these dogs (232 ng/L) was significantly lower than for those still alive at the end point of the study (556 ng/L). Hypocobalaminemia was relatively uncommon in this population of dogs with multicentric lymphoma, but was associated with a poor outcome. Serum cobalamin concentrations may provide prognostic information in dogs with multicentric lymphoma.

Association Study of Cobalamin Deficiency in the Chinese Shar Pei

Cobalamin deficiency is a common disorder in Chinese Shar Peis (Shar Peis) and is thus suspected to be hereditary. The objective of this study was to identify a genomic region or locus that cosegregates with the phenotype of cobalamin deficiency in Shar Peis. Serum cobalamin concentrations were measured, and blood for genomic DNA extraction was collected from 14 cobalamin-deficient Shar Peis and 28 Shar Peis with a serum cobalamin concentration in the reference range. The 327 microsatellite markers from the canine minimal screening set 2 and 4 additional markers were amplified by polymerase chain reaction and genotyped by automated capillary electrophoresis. Two microsatellite markers, DTR13.6 (P = 1.4 x 10(-6)) and REN13N11 (P = 1.5 x 10(-5)), both on canine chromosome 13, showed evidence of linkage disequilibrium. These findings indicate that the region of chromosome 13 near these markers should be mapped and closely examined for potential mutations associated with this disease in Shar Peis.

Serum cobalamin concentrations in healthy cats and cats with non‐alimentary tract illness in Australia

To determine a reference range for serum cobalamin concentration in healthy cats in Australia using a chemiluminescent enzyme immunoassay and to prospectively investigate the prevalence of hypocobalaminaemia in cats with non-alimentary tract disease. Prospective study measuring serum cobalamin concentrations in clinically healthy cats and cats with non-alimentary tract illness. Blood was collected from 50 clinically healthy cats that were owned by staff and associates of Veterinary Specialist Services or were owned animals presented to Creek Road Cat Clinic for routine vaccination. Blood was collected from 47 cats with non-alimentary tract illness presented at either clinic. Serum cobalamin concentration was determined for each group using a chemiluminescent enzyme immunoassay. A reference range for Australian cats calculated using the central 95th percentile in the 50 clinically healthy cats was 345 to 3668 pg/mL. Median serum cobalamin concentration in 47 cats with non-alimentary tract illness (1186 pg/mL; range 117-3480) was not significantly different to the median serum cobalamin of the 50 healthy cats (1213 pg/mL, range 311-3688). Using the calculated reference range one sick cat with non-alimentary tract illness had a markedly low serum cobalamin concentration. Although hypocobalaminaemia is uncommon in sick cats with non-alimentary tract illness in Australia, its occurrence in this study warrants further investigation.

In this issue – July 2009

Musculoskeletal disorders in Queensland veterinarians ▪ Australian surveillance for avian influenza viruses in wild birds ▪ Splenic lymphoma in an echidna ▪ Post‐thaw motility of equine semen ▪ Serum cobalamin concentrations in cats ▪ Acute toxicity of snail and slug bait in dogs ▪ Topical hydrocortisone aceponate for flea‐allergy dermatitis in dogs ▪ Activated coagulation times in normal cats and dogs ▪ Acquired arachnoid cyst in a cat

Relationships between Low Serum Cobalamin Concentrations and Methlymalonic Acidemia in Cats

Serum cobalamin concentrations below reference range are a common consequence of gastrointestinal disease in cats. Serum cobalamin <or= 100 ng/L is associated with methylmalonic acidemia. To determine the prevalence of cobalamin deficiency, defined by elevated serum methylmalonic acid (MMA), in cats with serum cobalamin <or= 290 ng/L, and the optimum serum cobalamin concentration to predict cobalamin deficiency in cats. SAMPLE SET: Residual serum samples (n = 206) from cats with serum cobalamin <or= 290 ng/L. Retrospective, observational study. Serum cobalamin and folate were measured with automated assays. Serum MMA was determined by gas chromatography-mass spectrometry. Cobalamin deficiency was defined as serum MMA > 867 nmol/L. Sensitivity and specificity of serum cobalamin concentrations <or=290 ng/L for detecting MMA > 867 nmol/L were analyzed using a receiver-operator characteristic curve. There was a negative correlation between serum cobalamin and MMA concentrations (Spearman's r=-0.74, P < 0.0001). The prevalence of MMA >or= 867 nmol/L in cats with serum cobalamin <or= 290 ng/L was 68.4%. Serum cobalamin <or= 160 ng/L had a 74% sensitivity and 80% specificity for detecting MMA > 867 nmol/L. No significant difference in serum folate concentrations was detected between affected and unaffected cats. Elevated MMA concentrations, suggesting cobalamin deficiency, are common in cats with serum cobalamin <or= 290 ng/L. Cobalamin deficiency is clinically significant, and supplementation with parenteral cobalamin is recommended for cats with gastrointestinal disease and low serum cobalamin concentrations.

Elevated canine pancreatic lipase immunoreactivity concentration in dogs with inflammatory bowel disease is associated with a negative outcome

To investigate whether elevated canine pancreatic lipase immunoreactivity (CPLI) concentrations in dogs with inflammatory bowel disease (IBD) is associated with a worse clinical outcome. Serum CPLI assays were performed on serum stored from cases diagnosed with IBD. Thirty-two dogs with CPLI results within the reference range were designated as the control group and 15 dogs had CPLI above the reference range. Clinical signs, age, serum lipase and amylase activities, serum albumin and cobalamin concentrations, abdominal ultrasound examination, histopathology on small intestinal biopsies, management of IBD and outcome were compared between the two groups. No significant differences were found in clinical activity score (P=0.54), number of antibiotic-responsive disease cases (P=0.480), number of steroid-responsive disease cases (P=0.491), serum amylase activity (P=0.058), serum cobalamin concentration (P=0.61), serum albumin concentration (P=0.052), abdominal ultrasound score (P=0.23) and histopathology scores for IBD (P=0.74) between the two groups. Dogs with increased CPLI concentration were significantly older and had a higher serum lipase activity than dogs with a CPLI concentration within the normal reference range (P=0.001, P=0.001, respectively). Moreover, dogs with increased CPLI concentration responded poorly to steroid treatment (P=0.01) and were significantly more likely to be euthanased at follow-up (P=0.02). CPLI should be measured in cases of canine IBD as elevated CPLI was associated with a worse outcome.

Prevalence of cobalamin deficiency in Afyonkarahisar elderly population

Objectives To determine whether there was an increased prevalence of low serum cobalamin concentrations in elderly people. Design and Methods Serum concentrations of cobalamin were measured in 202 elderly people. Results In the elderly group, cobalamin concentrations less than 191 pg/mL were found in 79 subjects (39.1%) compared with 24.5% of 19–40 years old subjects (n = 527) and 29.7% of 41–64 years old subjects (n = 1100) (p Conclusion The prevalence of cobalamin deficiency was 39.1% in Afyonkarahisar elderly population. Many elderly people with low serum cobalamin concentration had not had hematological findings.

Methylenetetrahydrofolate Reductase 677CT Polymorphism and Cobalamin, Folate, and Homocysteine Status in Spanish Adolescents

Background: Folate and cobalamin are responsible for healthy growth. However, the B-vitamin and homocysteine status of adolescents is not well known. The aim was to assess the status of folate, cobalamin, and homocysteine in healthy Spanish adolescents. Methods: Serum cobalamin, serum folate, homocysteine, methylenetetrahydrofolate reductase 677C>T variant, BMI, smoking habits, and Tanner stage were determined according to gender in 165 adolescents (84 females, 81 males; 13–18.5 years) using the Student’s t test, Mann-Whitney U test and χ² test, respectively. Interactions between socioeconomic status, age group, methylenetetrahydrofolate reductase polymorphism, BMI, smoking habits, Tanner stage, and vitamin status, respectively, were examined by ANOVA or Kruskal-Wallis H test (p < 0.05). Results: Boys had markedly higher homocysteine (males 8.92 (5.51–22.94) µmol/l; females 7.91 (5.09–13.86) µmol/l), whereas girls showed higher serum cobalamin concentrations (males 540.00 (268.00–946.47) pmol/l; females 594.82 (280.63–1,559.64) pmol/l). Data are shown as medians and the 2.5th to 97.5th percentiles in parentheses. Adolescents with the homozygous variant of methylenetetrahydrofolate reductase displayed significantly higher homocysteine and lower serum folate: normal 5.73 (3.09–10.73) ng/ml serum folate, 7.57 (4.94–12.94) µmol/l homocysteine; homozygous 4.10 (2.75–7.88) ng/ml serum folate, 10.83 (7.00–22.82) µmol/l homocysteine. Conclusion: The present study provides data on the folate, cobalamin, and homocysteine status of Spanish adolescents. To assure a better assessment, revision of references for adolescents is still needed.

Outcome of cats with low-grade lymphocytic lymphoma: 41 cases (1995–2005)

To evaluate factors associated with response to treatment, remission duration, and survival in cats with low-grade lymphoma affecting various organ systems. Retrospective case series. 41 cats with histologically confirmed low-grade lymphocytic lymphoma. Medical records and biopsy specimens of cats with histologically confirmed low-grade lymphocytic lymphoma of various organ systems treated with prednisone and chlorambucil between 1995 and 2005 were reviewed. The Kaplan-Meier method was used to estimate remission duration and survival. Factors potentially associated with prognosis were compared. Common clinical signs were weight loss (83%), vomiting (73%), anorexia (66%), and diarrhea (58%). Seventy-eight percent of cats tested had low serum cobalamin concentrations. Lymphoma was confined to the gastrointestinal tract in 68% of cats. Fifty-six percent of cats achieved a complete response to treatment, and 39% achieved a partial response. Five percent of cats had no response. No association was found between any risk factors (including anatomic site) and response to treatment. Partial response was associated with shorter remission duration, compared with complete response; median remission duration was 428 days for cats achieving a partial response, compared with 897 days for cats achieving a complete response. No other factors were associated with remission duration. Overall median survival time was 704 days. No factors were significantly associated with survival time. Most cats with lymphocytic lymphoma responded to treatment with prednisone and chlorambucil, and most factors evaluated were not associated with outcome.

Concentrations of vitamin C, vitamin B12 and folic acid in patients treated with hemodialysis and on-line hemodiafiltration or hemofiltration

Uncertainty has arisen as to whether vitamin supplements are needed by dialysis patients, in particular those treated by means of hemofiltration or hemodiafiltration using highly permeable (high-flux) filters. We therefore measured the concentrations of vitamin C, cobalamin (vitamin B12) and folic acid in conventional (low-flux) dialysis patients and in those receiving on-line treatment (hemofiltration or hemodiafiltration). Plasma (P-)ascorbate, serum (S-)cobalamin and S-folate concentrations were measured before and after a treatment session in 15 patients treated with low-flux hemodialysis and in 14 treated with on-line hemofiltration or hemodiafiltration. The patients' vitamin supplementations were also recorded. P-ascorbate concentrations were lowered by 51% and 53% in the hemodialysis and on-line groups, respectively after treatment and this reduction was significant (p<0.001). Concentrations below the reference values were found in 12/14 patients not receiving vitamin C supplementation. S-cobalamin did not decrease in the hemodialysis or on-line groups. S-folates did not change significantly in the hemodialysis or filtration groups. Patients without folacin supplementation had low values. P-ascorbate was reduced by both dialysis and filtration treatments. Neither S-cobalamin nor S-folate were reduced by dialysis or filtration treatments.

Prevalence of mild serum vitamin B12 deficiency in rural and urban Costa Rican young adults

Recent studies have shown an increase of mild serum cobalamin (vitamin B(12)) deficiency in some Latin American countries; however, no data are available from Costa Rica. The purpose of this work was to establish the prevalence of serum vitamin B(12) deficiency among Costa Rican young adults and to study some factors that may help explain the serum cobalamin concentrations. A cross-sectional survey was conducted among 400 adults aged 20 to 40 years old from urban and rural areas of the central valley of Costa Rica to determine serum vitamin B(12) levels. Additionally, cobalamin dietary intake and the detection of Helicobacter pylori IgG antibodies were studied as possible determinants of the serum vitamin B(12) concentrations. The mean serum concentration of vitamin B(12) was 268 +/- 125 pmol/L, and no significant differences were found by gender or area. Study data indicate an overall prevalence of inadequate serum cobalamin levels of 42.4% (11.2% deficient and 31.2% marginal); more than 50% but less than 75% of individuals had an intake of vitamin B(12) below the U.S. Estimated Average Requirement (EAR) and 61.2% had IgG antibodies to H. pylori. The prevalence of mild serum vitamin B(12) deficiency in young Costa Rican subjects is as high as in other Latin American countries. More investigation should be done to elucidate the etiological factors that are generating deficient and marginal serum cobalamin levels in Costa Rican adults in order to define appropriate public health actions.

MTHFR Gene polymorphisms, B-vitamins and hyperhomocystinemia in young and middle-aged acute myocardial infarction patients

We have examined the prevalence of the C677T and A1298C single nucleotide polymorphisms (SNPs) in the methylenetetrahydrofolate reductase (MTHFR) gene in healthy Tamilians and in patients with acute myocardial infarction and related this polymorphism to plasma homocysteine concentrations, serum folate, serum cobalamin and riboflavin status. The SNPs in the MTHFR gene were determined by polymerase chain reaction–restriction fragment length polymorphism analysis. Plasma homocysteine, serum folate and serum cobalamin concentrations were analyzed using an automated chemiluminescence method and riboflavin status was assessed by measuring the erythrocyte glutathione reductase activity using spectrophotometric method. Out of the 200 young and middle-aged (< 48 years) individuals included in the study, 100 were acute myocardial infarction (AMI) patients and 100 were healthy individuals with no documented history of heart diseases. There was a significant increase in homocysteine levels among the AMI patients as compared to the healthy controls ( p < 0.001). The results of this study indicate that hyperhomocystinemia is more prevalent in Tamilian AMI patients and that the MTHFR C677T and A1298C SNPs are not associated with hyperhomocystinemia. Folate status was found to be within normal range in all the study subjects. There was no correlation between homocysteine and different biochemical variables including cobalamin, folate and riboflavin. However, serum cobalamin was found to be significantly decreased in AMI patients when compared to controls ( p < 0.001). The simultaneous presence of decreased serum cobalamin status, hyperhomocystinemia and mutant genotype for both the SNPs might lead to an increased risk for the occurrence of AMI. Further intervention trials including the supplementation of cobalamin may prove whether homocysteine level decrease in response to the supplementation of cobalamin in individuals with hyperhomocystinemia and mutant genotype for both the above mentioned SNPs.

Holotranscobalamin, a New Early Marker Improves the Diagnostic Utility of the Macrocytic Anemia Panel Assays Performed on the Abbott AxSYM® Analyser.

A diagnosis of macrocytic anemia, a common blood disorder presenting in many forms, requires additional tests to determine the underlying cause. In particular, the prevalence of a sub-clinical functional Vitamin B12 (B12) deficiency in the general population is higher than expected. Treatment of B12 deficiency is important to prevent neurological and/or hematological complications but requires a reliable diagnosis. Total serum cobalamin concentrations may not reliably indicate B12 status. Several recent studies have reported that holotranscobalamin (HoloTC), the bio-available cobalamin fraction, would be an early indicator of B12 status with improved accuracy compared to total serum B12. We evaluated the diagnostic value of measurements of a macrocytic anemia panel (total B12, HoloTC, Folate and Homocysteine) in order to characterize populations at risk of metabolic cobalamin deficiency. Our observational study included 66 myelofibrosis patients (MF), 56 neurological patients (26 probable Alzheimer's disease, AD; 17 Mild Cognitive Impairment, MCI; 13 Vascular Disease,VaD), 20 vegans (V) and 16 apparently healthy volunteers (C) matched for age and sex. Serum concentrations of B12, Folate, and HoloTC were determined by microparticle enzyme immunoassay (MEIA); plasma Hcy levels were measured by fluorescence polarization immunoassay (FPIA) all on the Abbott AxSYM analyser. Hyperhomocysteinemia (>12 micromol/L) was present in 33.3% of MF (median 10.4, range 3.9–30.9); 38.5% of AD (median 11.4, range 7.1–46.5); 41.2% of MCI (median 12.0, range 8.3–16.4); 69.2% of VaD (median 15.0, range 6.6–23.6); 76.5% of V (median 14.2, range 5.9–31.5) and 33.3% of C (median 10.0, range 5.7–15.8). Low levels of B12 (< 180 pmol/L) were found in 10.6% of MF (median 471, range 137–959); 11.5% of AD (median 275, range 78–695); 11.8% of MCI (median 259, range 127–648); 15.4% of VaD (median 283, range 114–591); 10.6% of V (median 231, range 172–883) and 11.1 % of C (median 237, range 177–795). Low levels of HoloTC (< 35 pmol/L) were found in 43.9% of MF (median 46, range 14.9–123); 46.1% of AD (median 43, range 6.0–185); 52.9% of MCI (median 37, range 12–114); 23.1% of VaD (median 56, range 31–105); 82.3% of V (median 15.3, range 4.1–197) and 33.3 % of C (median 45, range 29–75). Vegans showed HoloTC levels significantly lower than all the other groups (p<0.02, Mann Whitney U test). Folate levels were considered not to add information in this context. Our preliminary findings clearly showed that HoloTC together with Hcy can help detect subjects likely to develop neurological and/or hematologic complications, and thereby likely to benefit from early tailored pharmacological treatment. In conclusion, HoloTC determination may be included as a complementary or alternative diagnostic strategy.Anemia Panel Results In At-Risk GroupsGroupHcy>12μmol/L(%)B12<180pmol/L (%)HoloTC<35pmol/L (%)MF33.310.643.9AD38.511.546.1MCI41.211.852.9VaD69.215.423.1V76.510.682.3C33.311.133.3

Detection of early abnormalities in gastric function in first‐degree relatives of patients with pernicious anemia*

Pernicious anemia (PA), as many other autoimmune disorders, has a trend to appear in other members of the family of the affected patients. Although this fact has been recognized since some decades ago, less is known about the frequency with which the abnormalities detected in the patients appear also in their relatives, the correlations that exist among these abnormalities and to what extent these markers of the disease relate to serum cobalamin concentration. For these reasons we studied the values of some markers of PA in a group of 79 first-degree relatives and we detected that the most frequent abnormalities are a decrease in serum pepsinogen I (22.7% of cases), an increase in serum gastrin (16.5% of cases) and in parietal cell antibody at a titer >or=40 (23.4% of cases). From a functional point of view, a decrease in hydrogen excretion in a magnesium breath test, indicative of achlorhydria, is also frequent (29.1%). The fall in cobalamin concentration runs in parallel with these abnormalities. The concentration of this vitamin was below normal levels in as much as 15.2% of cases. These findings emphasize the need for searching for the presence of occult or latent PA in relatives of patients with this diagnosis, not only to prevent the development of anemia but also to avoid other undesirable consequences of cobalamin deficiency.

Prospective evaluation of a peripherally administered three‐in‐one parenteral nutrition product in dogs

Peripheral parenteral nutrition is an option for short-term nutritional support in dogs which cannot be supported with enteral nutrition. The objective of this study was to examine the use of a three-in-one, 840 mOsmol/l peripheral parenteral nutrition product containing amino acids, lipids and glucose in separate compartments in dogs. Nine dogs were administered the three-in-one product, and two dogs were administered the amino acid part of the product, via a peripheral vein. Dogs were monitored for mechanical and metabolic complications. Mechanical complications (apparent thrombus or thrombophlebitis) caused failure of infusion at a median of 36 hours. None of the dogs appeared to develop catheter-related sepsis. Using a 10-hour infusion period appeared to decrease the incidence of line failure. Mild and clinically non-significant hyperglycaemia was the only metabolic complication. In four of the dogs, serum folate, cobalamin and homocysteine concentrations were determined before and after peripheral parenteral nutrition administration. Oral and parenteral administration of methionine has been previously associated with lowered serum folate concentrations. Low serum folates and the subsequent hyperhomocysteinaemia have been associated with venous endothelial damage and venous thrombus in other species. Serum cobalamin also affects homocysteine metabolism. Median serum folate, cobalamin and homocysteine concentrations were not affected by the short-term administration of this three-in-one product. Using the product for 24 hours/day may require catheter replacement due to line failure. Other than line failure, which may be improved by 10- to 12-hour infusion times, this product was found to be safe and practical for short-term peripheral parenteral nutrition in dogs.

Evaluation of cats fed vegetarian diets and attitudes of their caregivers

To determine motivation and feeding practices of people who feed their cats vegetarian diets as well as taurine and cobalamin status of cats consuming vegetarian diets. Cross-sectional study. 34 cats that had been exclusively fed a commercial or homemade vegetarian diet and 52 cats that had been fed a conventional diet for > or = 1 year. Participants were recruited through a Web site and from attendees of a national animal welfare conference. Caregivers of cats in both groups answered a telephone questionnaire regarding feeding practices for their cats. Blood was obtained from a subset of cats that had been fed vegetarian diets. Blood and plasma taurine and serum cobalamin concentrations were measured. People who fed vegetarian diets to their cats did so largely for ethical considerations and were more likely than people who fed conventional diets to believe that there are health benefits associated with a vegetarian diet and that conventional commercial cat foods are unwholesome. Both groups were aware of the potential health problems that could arise from improperly formulated vegetarian diets. All cats evaluated had serum cobalamin concentrations within reference range, and 14 of 17 had blood taurine concentrations within reference range. Vegetarian diets are fed to cats primarily for ethical considerations. Results of this study should aid practitioners in communicating with and providing advice to such clients.

Clinical significance of homocysteine in elderly hospitalized patients

Serum homocysteine levels, which increase with age, are now recognized as a vascular risk factor and are related to the development of heart failure and dementia in the elderly. However, relatively low serum homocysteine levels have also been reported to be an adverse prognostic factor in dialysis patients. The objective of the study was to analyze the prevalence, clinical significance, and prognostic value of serum homocysteine levels in patients older than 65 years, admitted to a general internal medicine hospitalization unit. We studied 337 hospitalized patients, 184 males and 153 females, aged 77.2 ± 0.4 years, whose admission was not determined by an acute vascular event. We recorded past vascular events and vascular risk factors. We determined the body mass index (weight in kilograms divided by the square of height in meters), and cholesterol, triglyceride, folate, vitamin B 12, and homocysteine levels. We also studied 36 control subjects (18 males and 18 females) of similar age. After discharge, we assessed the survival status of 301 patients by telephone recall. Survival curves were plotted by the method of Kaplan and Meier. Median survival was 1186 days. The 15th (9.6 μmol/L) and 50th (14.4 μmol/L) percentiles, as the lowest and highest cut-off points, were empirically defined as those related to a shorter survival. Serum homocysteine concentration was significantly positively correlated with age and serum creatinine and albumin concentrations, and negatively correlated with serum cobalamin and folate concentrations. The average serum homocysteine concentration for the patients group, as a whole, was 16.5 ± 0.5 μmol/L, not significantly different from the control group, but with a much greater dispersion, as patients with congestive heart failure or cognitive impairment had higher serum homocysteine concentrations, and patients with sepsis, leukocytosis, and hypoalbuminemia had lower concentrations. Malnutrition was associated both with abnormally high and low homocysteine concentrations, and abnormally low and abnormally high homocysteine concentrations were both associated with higher mortality. In conclusion, low homocysteine levels in elderly non–vitamin-supplemented hospitalized patients should not be interpreted as a protective factor in some individuals. Instead, it may be considered as an effect of an inflammatory-malnutrition process associated with a poor prognosis.

The Cobalamin-Binding Proteins Transcobalamin and Haptocorrin in Maternal and Cord Blood Sera at Birth

Two proteins carry vitamin B12 in plasma. Transcobalamin (TC) carries approximately 25% of total plasma vitamin B12 and is 6% to 20% saturated with cobalamin. Haptocorrin (HC) binds approximately 80% of total cobalamin and is largely saturated with cobalamin. We investigated the distribution and the relationship between concentrations of cobalamin, total and holo forms of TC, and HC in blood samples from pregnant women just before delivery (n = 92) and in cord blood samples from their newborn babies. We also investigated the relationship between these proteins and concentrations of methylmalonic acid (MMA), the functional marker of vitamin B12 status. Concentrations of total serum cobalamin, total HC, holoHC, and percentage of HC saturation were higher in cord blood than in the maternal blood (mean cobalamin, 268 vs 188 pmol/L; total HC, 648 vs 538 pmol/L; holoHC, 441 vs 237 pmol/L; HC saturation, 70% vs 47%). Moreover, total TC was low in cord blood, whereas both holoTC and TC saturation were higher in cord blood than in the maternal blood (mean total TC, 654 vs 1002 pmol/L; holoTC, 118 vs 53 pmol/L; TC saturation, 19.8% vs 5.4%). Higher maternal serum cobalamin was associated with higher cord blood holoTC and TC saturation (P <0.05). Gestational age was also a significant determinant of baby total TC, TC saturation, total HC, and holoHC. The close correlation between the amounts of holoTC present in cord blood and in maternal serum supports the importance of maternal cobalamin status for ensuring a sufficient supply to the baby.