The relationship of serum cobalamin to methylmalonic acid concentrations and clinical variables in cats

Signalment, clinicopathological findings, management practices and comorbidities in cats with diabetes mellitus in Germany: cross-sectional study of 144 cases

OBJECTIVES

The aim of this study was to describe signalment, clinicopathological findings, management practices and the occurrence of comorbidities in feline diabetes mellitus (DM) in Germany.

METHODS

This was a cross-sectional study using questionnaires and laboratory submissions to a commercial laboratory, Antech Lab Germany, between May 2021 and July 2022. Inclusion criteria were diagnosis of DM by the attending veterinarian and submission of a completed questionnaire besides blood samples. Laboratory testing included haematology, serum biochemistry, concentration of total thyroxine (TT4), insulin-like growth factor 1 (IGF-1), cobalamin (COB), fructosamine, b-hydroxybutyrate and DGGR (1,2-O-dilauryl-rac-glycero-3-glutaric acid-[6'-methylresorufin] ester) lipase activity. Data are presented as the median (range) and analysed by non-parametric tests. P <0.05 was considered statistically significant.

RESULTS

The median (range) age of the 144 diabetic cats at diagnosis was 11 years (0.9-18.7), 66.4% were male, 84.6% were domestic shorthair, 50.4% were currently overweight and 61.5% were previously overweight (body condition score >5/9). Most cats were treated with insulin (84%), most commonly protamine zinc insulin (57.5%). Blood glucose curves or continuous glucose monitoring alone or in combination with other methods were performed to adjust insulin therapy in 70.6% of cats. Based on questionnaires, 78.6% were poorly controlled and 21.4% were well controlled. Increased TT4 occurred in 3/139 and hyperthyroidism was known in 5/139 cats (frequency of known/suspected hyperthyroidism: 5.8% [n = 8/139]); 17.5% (n = 17/97) had increased IGF-1 (IGF-1 >746 ng/ml, cut-off for hypersomatotropism with the chemiluminescence assay used in this study); 24.5% (n = 34/139) had COB <295.2 pmol/l and 54.2% (n = 78/144) had increased DGGR. Cats with IGF-1 >746 ng/ml were receiving a higher insulin dose than cats with IGF-1 ≤746 ng/ml (median 1.63 vs 0.86 U/kg/day, P = 0.018).

CONCLUSION AND RELEVANCE

Increased DGGR and increased IGF-1 indicating hypersomatotropism are common in diabetic cats and should be tested for. Almost one-quarter of diabetic cats might require COB supplementation.

Plasma glucagon-like peptide-2 in cats with chronic enteropathies

OBJECTIVES

The objective of this study was to compare plasma glucagon-like peptide-2 (GLP-2) concentrations in cats with chronic enteropathies (CE) with those of healthy cats.

METHODS

Nineteen client-owned cats with a histopathologic diagnosis of either idiopathic chronic enteropathy (CIE) or low-grade lymphoma and six healthy client-owned cats were enrolled in a prospective study between 2 December 2021 and 9 June 2023. Fasted and postprandial plasma GLP-2 concentrations were measured via ELISA in CE cats at the time gastrointestinal biopsies were obtained and before CE treatment. In cats with a histopathologic diagnosis of CIE, plasma GLP-2 concentrations were re-evaluated after 1 month of CE treatment.

RESULTS

There was no significant difference in plasma GLP-2 concentrations between healthy cats (0.53 ng/ml) and cats with CE (0.52 ng/ml). GLP-2 concentrations in cats with CIE were not significantly different following 1 month of treatment (0.43 ng/ml) from those at initial presentation (0.44 ng/ml).

CONCLUSIONS AND RELEVANCE

GLP-2 can be successfully detected in the plasma of cats with CE. Based on the lack of differences observed between this population of CE cats and healthy cats, GLP-2 cannot be recommended as a biomarker of feline CE using this ELISA method. Further investigation of larger CE cat populations and analytic methods would be needed to determine the overall utility of GLP-2 evaluation in feline CE.

Effect of oral or subcutaneous administration of cyanocobalamin in hypocobalaminemic cats with chronic gastrointestinal disease or exocrine pancreatic insufficiency

BACKGROUND

No prospective study has evaluated the efficacy of oral supplementation with cobalamin in hypocobalaminemic cats.

OBJECTIVES

To investigate the efficacy of oral or SC supplementation with cyanocobalamin in normalizing serum cobalamin and methylmalonic acid (MMA) concentrations in hypocobalaminemic cats with chronic gastrointestinal disease (CGID) or exocrine pancreatic insufficiency (EPI).

ANIMALS

Forty-eight client-owned hypocobalaminemic (<290 ng/L) cats with normal or abnormally high serum MMA concentrations.

METHODS

This study was conducted based on the prospective randomized clinical trial method. Cats with CGID or EPI were randomly assigned to 2 groups that received either oral or SC supplementation with cobalamin (250 μg/cat) for 12 and 10 weeks, respectively, in addition to other medical and dietary interventions. Each cat was evaluated 3 times (baseline, 6-week postsupplementation, and 1-week postcompletion) by measuring serum cobalamin and MMA concentrations.

RESULTS

In cats with CGID or EPI, cobalamin concentrations were normalized in all cats that received either oral or SC supplementation (mean 100% [95% CI: 80.6%-100%] in both groups in cats with CGID and 100% [67.6%-100%] in both groups in cats with EPI). Among 37 cats with elevated MMA concentrations at baseline (21 cats with CGID and 16 cats with EPI), MMA concentrations were normalized in most cats with CGID (70% in oral and 82% in SC group) or EPI (88% in both groups).

CONCLUSIONS AND CLINICAL IMPORTANCE

In hypocobalaminemic cats with CGID or EPI, in conjunction with other medical and dietary interventions, both oral and SC supplementation are effective at normalizing serum cobalamin and MMA concentrations.

Hypocobalaminaemia in dogs with acute gastrointestinal diseases

OBJECTIVES

The objectives of this study were to investigate the prevalence of hypocobalaminaemia in dogs with acute gastrointestinal diseases and to evaluate its relationship with disease severity and outcome.

MATERIALS AND METHODS

Medical records of dogs presented for acute gastrointestinal signs that a serum cobalamin concentration measured between September 2019 and 2021 were included in this study. Hypocobalaminaemia was defined as serum cobalamin concentration <200 pmol/L, and low-normal cobalamin was defined as serum cobalamin concentration of 200 to 295 pmol/L. Duration of clinical signs prior to presentation, Acute Patient Physiologic and Laboratory Evaluation (APPLE) fast score, length of hospitalisation and outcome were recorded.

RESULTS

Thirty-three dogs were included. Seventeen dogs were diagnosed with acute gastrointestinal disease of unknown aetiology, seven dogs with parvoviral enteritis, three dogs with acute haemorrhagic diarrhoea syndrome and six dogs with miscellaneous diseases. The prevalence of hypocobalaminaemia in this population was 30.3% and low-normal cobalamin concentration was detected in 18.2% of dogs. There was no statistically significant relationship between the detection of hypocobalaminaemia or low-normal cobalamin and the duration of clinical signs before presentation, length of hospitalisation or Acute Patient Physiologic and Laboratory Evaluation fast score on admission. Mortality rate was 3%.

CLINICAL SIGNIFICANCE

Hypocobalaminaemia and low-normal cobalamin are common findings in dogs with acute gastrointestinal diseases. The therapeutic significance and potential implications for prognosis of hypocobalaminaemia in these patients requires further investigation.

Splenic torsion in a cat with chronic anemia

Case summary

A 4-year-old female spayed domestic shorthair cat with chronic anemia was evaluated for acute-onset lethargy, vomiting, abdominal distension, and a palpably enlarged and firm spleen. Abdominal ultrasound confirmed marked splenomegaly and concern for a splenic infarct, prompting exploratory abdominal surgery, where splenic torsion was diagnosed. A splenectomy was performed, and the cat recovered uneventfully. Splenitis was diagnosed on histopathology. Anemia improved postoperatively. The role of chronic anemia and other concurrent findings in the development of splenic torsion in this case remains unknown.

Relevance and novel information

Splenic torsion has not been previously reported in cats, making this the first case of its kind. In cases of splenomegaly and abnormal splenic blood flow, splenic torsion should be considered a differential diagnosis in cats.

ACVIM consensus statement guidelines on diagnosing and distinguishing low-grade neoplastic from inflammatory lymphocytic chronic enteropathies in cats

BACKGROUND

Lymphoplasmacytic enteritis (LPE) and low-grade intestinal T cell lymphoma (LGITL) are common diseases in older cats, but their diagnosis and differentiation remain challenging.

OBJECTIVES

To summarize the current literature on etiopathogenesis and diagnosis of LPE and LGITL in cats and provide guidance on the differentiation between LPE and LGITL in cats. To provide statements established using evidence-based approaches or where such evidence is lacking, statements based on consensus of experts in the field.

ANIMALS

None.

METHODS

A panel of 6 experts in the field (2 internists, 1 radiologist, 1 anatomic pathologist, 1 clonality expert, 1 oncologist) with the support of a human medical immunologist, was formed to assess and summarize evidence in the peer-reviewed literature and complement it with consensus recommendations.

RESULTS

Despite increasing interest on the topic for clinicians and pathologists, few prospective studies were available, and interpretation of the pertinent literature often was challenging because of the heterogeneity of the cases. Most recommendations by the panel were supported by a moderate or low level of evidence. Several understudied areas were identified, including cellular markers using immunohistochemistry, genomics, and transcriptomic studies.

CONCLUSIONS AND CLINICAL IMPORTANCE

To date, no single diagnostic criterion or known biomarker reliably differentiates inflammatory lesions from neoplastic lymphoproliferations in the intestinal tract of cats and a diagnosis currently is established by integrating all available clinical and diagnostic data. Histopathology remains the mainstay to better differentiate LPE from LGITL in cats with chronic enteropathy.

Vitamin B12 in Cats: Nutrition, Metabolism, and Disease

Cobalamin is a water-soluble molecule that has an important role in cellular metabolism, especially in DNA synthesis, methylation, and mitochondrial metabolism. Cobalamin is bound by intrinsic factor (IF) and absorbed in the ileal tract. The IF in cats is synthesized exclusively by pancreatic tissue. About 75% of the total plasma cobalamin in cats is associated with transcobalamin II, while in this species, transcobalamin I is not present. In cats, the half-life of cobalamin is 11-14 days. Diagnostic biomarkers for B12 status in cats include decreased levels of circulating total cobalamin and increased levels of methylmalonic acid. The reference interval for serum cobalamin concentrations in cats is 290-1500 ng/L, and for the serum methylmalonic acid concentration, it is 139-897 nmol/L. Therapy for hypocobalaminemia mainly depends on the underlying disease. In some cases, subcutaneous or intramuscular injection of 250 μg/cat is empirically administered. In recent years, it has been demonstrated that oral cobalamin supplementation can also be used successfully in dogs and cats as a less invasive alternative to parental administration. This review describes the current knowledge regarding B12 requirements and highlights improvements in diagnostic methods as well as the role of hypocobalaminemia in its associated diseases.

Serial Measurement of Serum Pancreatic Lipase Immunoreactivity, Feline Trypsin-like Immunoreactivity, and Cobalamin Concentrations in Kittens

Serum concentrations of feline pancreatic lipase immunoreactivity (fPLI), feline trypsin-like immunoreactivity (fTLI), and cobalamin are commonly used for the diagnostic investigation of cats with gastrointestinal signs. No information on these parameters in healthy cats less than 1 year of age exists. We aimed to evaluate serum concentrations of fPLI, fTLI, and cobalamin in healthy cats at different time-points during their first 12 months of life. Fourteen healthy 2-month-old kittens were included. Blood was collected at 2, 3, 4, 6, and 12 months of age, and serum concentrations of fPLI, fTLI, and cobalamin were measured. While there was a statistically significant difference in serum fPLI concentrations over time, there was no statistically significant difference between individual time-points. There was no significant difference in serum fTLI concentrations over time. Serum cobalamin concentrations were below the reference interval in 3/13 cats at 2 months of age and were significantly lower by 3 months, when 13/14 had hypocobalaminemia. By 12 months, serum cobalamin had significantly increased, yet 4/12 cats still had hypocobalaminemia. Serum fPLI and fTLI concentrations did not show any statistically or clinically significant differences in young kittens. In contrast, serum cobalamin concentrations were commonly below the reference interval in kittens. Serum fPLI and fTLI concentrations are not practically affected by age in kittens as young as 2 months of age and could be used for the investigation of pancreatic diseases.

Hyperammonemia in azotemic cats

OBJECTIVES

Hyperammonemia occurs in cats with hepatobiliary and nutritional (cobalamin and arginine deficiency) disorders, and has also been documented in four cats with renal azotemia. We hypothesized that in cats with renal azotemia, fasting hyperammonemia would correlate with indices of worsening kidney function, and would be independent of cobalamin, potassium, systemic inflammation or urinary tract infection (UTI) with urease-producing bacteria.

METHODS

A fasted blood sample was prospectively collected for ammonia and cobalamin analysis from 18 client-owned cats with renal azotemia (creatinine [Cr] ⩾1.6 mg/dl, urine specific gravity <1.030 or documentation of historical chronic kidney disease [CKD]). Correlations between blood ammonia and selected biochemical parameters were analyzed using Pearson's correlation coefficient.

RESULTS

Seven castrated males and 11 spayed females with a median age of 12 years (range 4-19 years) were enrolled. Ten of 18 (56%) cats presented for acute kidney injury (AKI) or acute on chronic kidney disease (AoCKD), and 8/18 (44%) presented for progressive CKD. The median Cr was 5.9 mg/dl (range 1.9-24.7 mg/dl). Hyperammonemia was documented in 4/18 (22%) cats, with a median of 95 µmol/dl (range 85-98 µmol/dl), and all four of these cats were classified as AKI/AoCKD. Blood ammonia concentrations had a significant moderate positive correlation between blood urea nitrogen (BUN) (r = 0.645, P = 0.003), Cr (r = 0.578, P = 0.012) and serum phosphorus (r = 0.714, P = 0.0009) but not with cobalamin, potassium or white blood cell count. No cats had UTIs with urease-producing bacteria.

CONCLUSIONS AND RELEVANCE

A correlation exists between blood ammonia and BUN, Cr and phosphorus in cats with renal azotemia. Future studies are warranted in a larger population of cats to determine the true prevalence, etiology and potential therapeutic effect of medical management of hyperammonemia on long-term prognosis in cats with kidney disease.

Anemia, iron deficiency, and cobalamin deficiency in cats with chronic gastrointestinal disease

BACKGROUND

Iron deficiency and cobalamin deficiency, as sequelae to chronic gastrointestinal (GI) disease, could result in anemia and increased morbidity in cats with chronic enteropathies.

OBJECTIVE

To evaluate iron deficiency in cats with chronic GI disease and its relationship with hypocobalaminemia, anemia, and disease severity.

ANIMALS

Twenty client-owned cats with primary GI disease.

METHODS

Prospective, cross-sectional study. Cats were enrolled at the time of evaluation for chronic GI disease, after exclusion of comorbidities. CBC with reticulocyte indices, iron metabolism (serum iron and ferritin concentrations, total iron binding capacity [TIBC]), serum methylmalonic acid (MMA), cobalamin, and folate concentrations, pancreatic lipase and trypsin-like immunoreactivity, and disease severity were evaluated.

RESULTS

Anemia (hematocrit <30%), iron deficiency, and cobalamin deficiency were diagnosed in 4/20, 7/20, and 8/20 cats, respectively. Hematocrit (r_s = -.45; P < .05) and body condition score (r_s = -.60; P < .01) negatively correlated with MMA. Median TIBC was lower in cats with increased vs normal MMA (218 μg/mL; range, 120-466 μg/mL vs 288 μg/mL; range, 195-369 μg/mL; P = .02). Hematocrit (r_s = .51; P = .02), reticulocyte MCV (r_s = .52; P = .02), reticulocyte hemoglobin content (r_s = .71; P < .001), and percent transferrin saturation (r_s = .79; P < .0001) positively correlated with serum iron concentration.

CONCLUSIONS AND CLINICAL IMPORTANCE

Functional iron deficiency was common in cats with chronic GI disease. Associations between hypocobalaminemia, iron parameters, and hematologic parameters warrant further investigation on the impact of iron deficiency on chronic GI disease morbidity in cats.

Efficacy of intramuscular hydroxocobalamin supplementation in cats with cobalamin deficiency and gastrointestinal disease

Background

In humans, absorption and tissue retention rates of intramuscularly administered hydroxocobalamin (OH‐Cbl) are superior compared to cyanocobalamin (CN‐Cbl). Supplementation with OH‐Cbl has not been described in cats.

Objectives

To evaluate effects of parenteral OH‐Cbl supplementation on clinical signs, serum Cbl and methylmalonic acid (MMA) concentrations in hypocobalaminemic cats with gastrointestinal disease.

Animals

Twenty‐three client‐owned cats.

Methods

Prospective study. Serum Cbl and MMA concentrations were determined at enrollment (t0), immediately before the 4th OH‐Cbl IM injection (300 μg, given q2 weeks) (t1), and 4 weeks after the 4th injection (t2). Severity of clinical signs (activity, appetite, vomiting, diarrhea, body weight) was graded at each time point and expressed as clinical disease activity score.

Results

Median clinical disease activity score decreased significantly from t0 (6; range, 2‐10) to t1 (1; range, 0‐6) and t2 (1; range, 0‐9). Median serum Cbl concentration increased significantly from 111 pmol/L (range, 111‐218; reference range, 225‐1451 pmol/L) at t0 to 1612 pmol/L (range, 526‐14 756) (P < .001) at t1, and decreased again significantly to 712 pmol/L (range, 205‐4265) (P < .01) at t2. Median baseline serum MMA concentration at t0 (802 nmol/L; range, 238‐151 000; reference range, 120‐420 nmol/L) decreased significantly (P < .001) to 199 nmol/L (range, 29‐478) at t1, and was 205 nmol/L (range, 88‐734) at t2. Serum MMA concentrations normalized in 22/23 cats at t1, and were not significantly higher at t2 compared to t1.

Conclusions and Clinical Importance

The herein described OH‐Cbl injection scheme appears efficacious for normalization of cellular Cbl deficiency in cats with gastrointestinal disease.

Time course of serum cobalamin, folate, and total iron binding capacity concentrations in pregnant bitches and association with hematological variables and survival

Background

Hypocobalaminemia, hypofolatemia and iron deficiency are associated with pregnancy‐related anemia (PRA) and neonatal survival (NS) in women. Similar associations have not been investigated in pregnant bitches.

Objectives

To investigate time course and associations of serum cobalamin, folate and iron status indicators with hematological variables and NS in pregnant bitches.

Animals

Forty‐eight pregnant bitches.

Methods

A prospective cohort study. Pregnancy was confirmed by abdominal ultrasonography twice during mid‐ and late pregnancy, concurrently with blood sampling. Associations among pregnancy stage, NS and laboratory variables were assessed by generalized estimating equations.

Results

Compared with midpregnancy, serum cobalamin (adjusted mean [95% confidence interval, CI]) decreased at late pregnancy (430 pg/mL [394‐466] versus 330 pg/mL [303‐357], respectively; P < .001), whereas serum folate did not. Every increment of 1 in parity number or litter size corresponded to 28.6 pg/mL (95% CI, 5.6‐51.6; P = .02) and 20.3 pg/mL (95% CI, 10.9‐29.7; P < .001) decrease in serum cobalamin concentration. Compared with midpregnancy, serum iron (P < .001) and transferrin saturation (P = .01) increased at late pregnancy. The decrease in red blood cell count (P < .001) at late pregnancy was significantly, albeit weakly, correlated with decreasing serum folate concentration (r = 0.33; P = .02). None of the measures was associated with NS.

Conclusions and Clinical Significance

Pregnancy‐related anemia was common at late pregnancy. Unlike in women, in pregnant bitches, serum iron and transferrin saturation were increased at late pregnancy. Future studies are warranted to investigate the clinical ramifications of hypocobalaminemia in pregnant bitches and the utility of prophylactic folate administration in mitigating PRA.

Effects of storage conditions and duration on cobalamin concentration in serum samples from cats and dogs

OBJECTIVE To evaluate the effects of storage conditions and duration on cobalamin concentration in serum samples from dogs and cats. DESIGN Experiment. SAMPLE Serum samples from 9 client-owned cats and 9 client-owned dogs. PROCEDURES Serum harvested from freshly obtained blood samples was separated into 11 aliquots/animal. One aliquot (baseline sample) was routinely transported in light-protected tubes to the laboratory for cobalamin assay; each of the remaining aliquots was stored in a refrigerator (6°C; n = 5) or at room temperature (20°C) with exposure to daylight (5) for 24, 48, 72, 96, or 120 hours. Aliquots were subsequently wrapped in aluminum foil, frozen (-20°C), and then transported to the laboratory for measurement of cobalamin concentration, all in the same run. Percentage decrease in cobalamin concentration from baseline was analyzed by means of linear mixed modeling. RESULTS No differences in cobalamin values were identified between cats and dogs; therefore, data for both species were analyzed together. Median baseline serum cobalamin concentration was 424 ng/L (range, 178 to 1,880 ng/L). Values for serum samples stored with daylight exposure at room temperature were significantly lower over time than were values for refrigerated samples. Although values for refrigerated samples did not decrease significantly from baseline values over time, values for the other storage condition did; however, the mean percentage decrease for serum samples stored at room temperature was small (0.14%/h; 95% confidence interval, 0.07% to 0.21%/h). CONCLUSIONS AND CLINICAL RELEVANCE Overall, serum cobalamin concentration appeared stable for 5 days when feline and canine serum samples were refrigerated at 6°C. The effect of light and room temperature on serum cobalamin concentration, although significant, was quite small for samples stored with these exposures for the same 5-day period.

Relationship between cobalamin and folate deficiencies and anemia in dogs

Background

Megaloblastic, nonregenerative anemia is a well‐known consequence of cobalamin or folate deficiencies in humans but is not recognized in hypocobalaminemic or hypofolatemic dogs. Establishment of relationships between hypocobalaminemia or hypofolatemia and hematologic disease would encourage vitamin B testing, and potentially supplementation, in anemic dogs.

Objectives

To determine the prevalence of anemia in hypocobalaminemic or hypofolatemic dogs and to report the prevalence of hypocobalaminemia and hypofolatemia and nonregenerative anemia, macrocytosis, and anisocytosis in anemic dogs.

Animals

One hundred and fourteen client‐owned dogs with known serum cobalamin and folate concentrations and CBCs and 42 client‐owned anemic dogs.

Methods

Retrospective comparison of anemia prevalence in hypocobalaminemic or hypofolatemic and normocobalaminemic or normofolatemic dogs was performed. Prospective measurement of erythrocyte variables and cobalamin and folate concentrations in anemic dogs was carried out; relationships among hypocobalaminemia and regenerative status, mean corpuscular volume, and red cell distribution width were evaluated.

Results

Significant differences in prevalence of anemia between hypocobalaminemic (36%) and normocobalaminemic dogs (26%; P = .23) or between hypofolatemic (31%) and normofolatemic dogs (30%; P = .99) were not detected. Between hypocobalaminemic and normocobalaminemic dogs, no significant differences in prevalence of nonregenerative anemia (69% vs 63%; P = .65), macrocytosis (17% vs 0%; P = .53), or anisocytosis (28% vs 0%; P = .14) were detected. Anemic dogs had high prevalence of vitamin B deficiencies (nonregenerative: 64% hypocobalaminemic, 18% hypofolatemic; regenerative: 57% hypocobalaminemic, 21% hypofolatemic).

Conclusions and Clinical Importance

The association between cobalamin and folate deficiencies and macrocytic, nonregenerative anemia established in humans is not routinely present in dogs.

Correlation between the FCEAI and diagnostic parameters in chronic enteropathies in 147 cats (2006-2012)

OBJECTIVE

The Feline Chronic Enteropathy Activity Index (FCEAI) has been established as a quantitative index for disease activity in chronic enteropathies in cats. A definite diagnosis is aimed at histology with initial exclusion of extraintestinal causes by laboratory examinations, diagnostic imaging and endoscopy. The study aimed to examine diagnostic parameters and FCEAI in chronic gastroenteropathies.

MATERIALS AND METHODS

A retrospective case review of 147 cats with chronic enteropathies was performed. In all patients, the FCEAI was established and endoscopy performed including biopsies and duodenal cytology. Histopathologic reports were reviewed for the diagnosis of lymphoma and architectural changes (epithelial integrity, villi/gland atrophy, intestinal crypt atrophy, lymphangiectasia, epitheliotropism/infiltration of intraepithelial lymphocytes). A cytopathologic score (CS) and histopathologic score (HS) regarding lymphocytic intestinal infiltration were assigned. Statistical dependency analysis was used to determine correlations between the FCEAI, lymphoma, architectural changes, CS, HS, serum concentrations of cobalamin, folate and albumin.

RESULTS

The 147 cats consisted of predominately European Shorthair cats (n = 126), were mostly castrated (n = 127) and had a mean age of 9.8 (1-17) years. For the proven lymphoma group (12.2%; n = 18) and the non-lymphoma group a mean FCEAI of 7.3 (4-17) and 6.6 (2-13), respectively, was established. The FCEAI showed a low correlation with the CS (p = 0.010; R = 0.22) and intestinal villous atrophy (n = 121; p = 0.035; R = 0.19). Cats with a CS of 0 had a significant lower FCEAI score (p = 0.015) than cats with all other CSs. The histo- and cytopathologic scores were highly related (p < 0.001; R = 0.43). The gastric intraepithelial lymphocytic infiltration (n = 131) was significantly correlated to serum folate (p = 0.014; R = -0.56) and albumin (p = 0,048; R = -0.20).

CONCLUSION

The FCEAI showed only a few correlations. Not only the grade of inflammation, but also the histologic architectural changes are of importance.

Effects of 6 Weeks of Parenteral Cobalamin Supplementation on Clinical and Biochemical Variables in Cats with Gastrointestinal Disease

Background

Effects and duration of commonly used protocols for cobalamin (Cbl) supplementation on cellular Cbl deficiency have not been determined in hypocobalaminemic cats.

Hypothesis/Objectives

To evaluate effect of Cbl supplementation on clinical signs, serum and urine methylmalonic acid (MMA) concentrations over 16 weeks.

Animals

Twenty client‐owned hypocobalaminemic cats with enteropathy.

Methods

Prospective study. Serum Cbl and serum and urine MMA concentrations were determined prospectively in cats at enrollment (t0), immediately before (t6), and 4 (t10) and 10 weeks (t16) after 6th Cbl injection (250 μg, IM q 7 days). Clinical signs severity (activity, appetite, vomiting, diarrhea, body weight) graded at each time point and expressed as clinical disease activity score.

Results

Clinical disease activity score decreased during supplementation and increased after treatment discontinuation. Median serum Cbl concentration increased significantly from t0 (111 pmol/L, range 111–212) to t6 (2,332.5 pmol/L, range 123–22,730) (P < 0.01). Values at t10 were 610.5 pmol/L (range, 111–2,527) and 180.5 pmol/L (range, 111–2,262) at t16 (P < 0.01). Median baseline serum MMA concentration (372 μmol/L, range 0.39–147,000) decreased significantly to 1.62 μmol/L (range, 0.18–806) at t6 (P < 0.01) and gradually increased to 5.34 μmol/L (range, 0.13–1,730) at t10 and 189 μmol/L (range, 0.4–983) at t16. Similar, nonsignificant, pattern observed for urine MMA concentration. Serum and urine MMA concentrations had not normalized in 12 and 6 cats, respectively, at t6.

Conclusion and Clinical Importance

The Cbl supplementation protocol used here did not lead to complete normalization of cellular Cbl deficiency in all examined cats, and biochemical improvements were transient.

Serum cobalamin concentrations and small intestinal ultrasound changes in 75 cats with clinical signs of gastrointestinal disease: a retrospective study

Objectives The aim of the study was to evaluate ultrasonographic changes in the small intestine of cats with clinical signs of gastrointestinal disease and low or low-normal serum cobalamin concentrations. Methods Records for client-owned cats presenting to the small animal hospital with signs of gastrointestinal disease and in which serum cobalamin concentrations were measured from 2000-2013 were reviewed. Inclusion criteria were cobalamin concentrations <500 ng/l, abdominal ultrasound within 1 month of cobalamin testing and definitive diagnosis. Results Of 751 serum cobalamin measurements, hypocobalaminemia or low-normal cobalamin was identified in 270 cats, abdominal ultrasound was performed in 207 of those cats and a diagnosis was available for 75 of them. Small intestinal ultrasound changes were detected in 49/75 (65%) cats. Abnormalities included thickening, loss of wall layer definition, echogenicity alterations and discrete masses. Serum cobalamin concentrations <500 ng/l were observed with diagnoses of inflammatory disease, neoplasia, infectious disease and normal histopathology. Cobalamin concentration was significantly lower in cats with lymphoma or inflammatory bowel disease compared with other gastrointestinal neoplasia ( P = 0.031). No difference was found between cobalamin concentration and the presence of ultrasound abnormalities, specific ultrasound changes or albumin concentration. Conclusions and relevance One-third of symptomatic cats with hypocobalaminemia or low-normal cobalamin concentrations may have an ultrasonographically normal small intestine. For the majority of cats in this study, histopathologic abnormalities were observed in the small intestine, regardless of ultrasound changes. These findings suggest gastrointestinal disease should not be excluded based on low-normal cobalamin concentrations, even with a concurrent normal ultrasound examination. Additional studies are needed in cats with low-normal serum cobalamin concentrations, as a definitive diagnosis was not pursued consistently in those cats. However, data from this study suggest that careful monitoring, histopathologic evaluation and future cobalamin supplementation may be warranted.

Hypercobalaminaemia is associated with hepatic and neoplastic disease in cats: a cross sectional study

Background

When increased serum cobalamin concentrations are encountered clinically they are usually attributed to parenteral supplementation, dietary factors, or otherwise ignored. However, recently, hypercobalaminaemia has been associated with numerous diseases in humans, most notably neoplastic and hepatic disorders. The aim of this retrospective, observational, cross-sectional study was to determine the significance of increased cobalamin in cats.

Results

In total, 237 records were retrieved and 174 cats, of various ages and sexes met the inclusion criteria. A total of 42 cats had increased serum cobalamin concentration, and had not received prior supplementation. Multiple logistic regression analysis revealed that increased serum cobalamin concentration was positively related to pedigree breed (pedigree breeds more likely to have increased cobalamin concentration, odds ratio [OR] 4.24, 95% CI 1.78-10.15, P = 0.001), to having liver disease (OR 9.91, 95% CI 3.54-27.68), and to having a solid neoplasm (OR 8.54, 95% CI 1.10-66.45).

Conclusions

The results of the current study suggest that increased serum cobalamin concentrations should not be ignored in cats with no history of supplementation, and investigation for underlying hepatic or neoplastic disease is warranted.