Pegylated-l-asparaginase therapy for feline large cell lymphoma: 82 cases (2017-2020).

OBJECTIVES: The present study aimed to investigate pegylated-l-asparaginase monotherapy for feline large cell lymphoma as a potential alternative to palliative corticosteroids treatment in animals whose owners declined cytotoxic chemotherapy. METHODS: A retrospective, descriptive case series of cats treated initially with pegylated-l-asparaginase as a sole therapy for feline large cell lymphoma is reported. The treatment protocol consisted of 12 intramuscular injections of pegylated-l-asparaginase with increasing intervals. If cats were unresponsive to pegylated-l-asparaginase monotherapy, a second-line treatment was initiated. Signalment, origin of lymphoma, staging, treatment, possible adverse events and follow-up data were extracted from the medical records. Responses and survival data were analysed. RESULTS: Eighty-two cats with lymphoma of five different anatomic types were included: alimentary, abdominal extra-alimentary, peripheral nodal, nasal/nasopharyngeal and other (mediastinal, renal [solitary] and miscellaneous combined in one group for analytical purposes). The response rate was 74.1% (95% confidence interval = 63.4-83.5) with 38.3% (95% confidence interval = 27.8-48.8) in complete remission. The median disease-free period and calculated overall survival time were 70 days (12-1702+) and 79 days (1-1715+), respectively. The response rate was significantly correlated with the origin of the lymphoma and the combined group had a significantly lower response rate (P = 0.035). Twenty-four cats were also treated with corticosteroids. There was no significant difference in outcomes between the group treated with or without corticosteroids. Adverse events were present in a small number of cats (14/82). The majority of these adverse events were mild to moderate in 5/14 cats; however, the adverse events were severe enough to cause discontinuation of therapy. CONCLUSIONS AND RELEVANCE: Based on the response rate and median disease-free period, treatment with pegylated-l-asparaginase is inferior when compared with historical chemotherapy protocols. However, some cats demonstrated an exceptional long disease-free period. Therefore, pegylated-l-asparaginase could be offered as an alternative to corticosteroid therapy alone. Further studies are needed to evaluate the additional benefit over palliative corticosteroid monotherapy.

Quality of life and response to treatment in cats with hypersomatotropism: the owners' point of view.

OBJECTIVES: The aim of this study was to collect clinical information from owners of cats with hypersomatotropism (HS) distributed worldwide, assessing the impact of HS and its treatments on cats' quality of life (QoL) and survival time. METHODS: A survey focused on clinical presentation, diagnostic procedures, treatments, cats' QoL and disease progression was distributed worldwide to owners of cats with HS. The owner's perception of the cats' QoL before and after or during treatment was defined using a score ranging from 1 (poor) to 5 (excellent). Improvement following treatment (IFT) was quantified using a score ranging from 1 (absent) to 5 (obvious). Different treatment groups, including at least five cases, were compared. RESULTS: A total of 127 cats were included from at least 11 different countries. Among these, 120 (95%) were diabetic and 7 (5%) were not. Out of 120 diabetic cats, 55 (46%) were treated with insulin as a single treatment (INS). Other treatments were not mentioned to owners in 35/120 (29%) cases. The median QoL score at diagnosis was 2 (range 1-5) and improved after treatment in all groups. Cabergoline (4; range 1-5), radiotherapy (4; range 2-5) and hypophysectomy (5; range 4-5) showed better median IFT scores compared with INS (3; range 1-5) (P = 0.046, P <0.002 and P <0.0001, respectively). Hypophysectomy IFT proved superior to cabergoline (P = 0.047) and was equal to radiotherapy IFT (P = 0.32). No difference was found between cabergoline and radiotherapy IFT (P = 0.99). The median survival time (MST) was 24 months (range 0-75 months). Cats treated with INS showed shorter MST (22 months; range 0-69 months) compared with cats treated with causal treatments combined (36 months; range 3-75 months) (P = 0.04). CONCLUSIONS AND RELEVANCE: Not all cats with HS will have diabetes mellitus. Causal treatments seem associated with the greatest improvements in perceived cats' QoL and survival; such treatments should therefore be discussed with owners. Cabergoline could be an effective alternative management option.

Diabetes mellitus remission in three cats with hypersomatotropism after cabergoline treatment.

CASE SUMMARY: Three diabetic cats presented with polyuria, polydipsia, polyphagia and poor glycemic control. Cat 1 displayed prognathia inferior and had a body condition score (BCS) of 4/5; cat 2 had a BCS of 5/5; and cat 3 had broad facial features. Serum insulin-like growth factor 1 concentrations were compatible with hypersomatotropism in cat 1 and cat 2 (>1500 ng/ml and 1200 ng/ml, respectively) and just below the cut-off of 1000 ng/ml (947 ng/ml) in cat 3; in this last cat diagnosis was further supported by the presence of pituitary enlargement on MRI. Oral cabergoline (10 µg/kg q48h) was initiated. Insulin requirements progressively reduced, as evidenced by daily blood glucose monitoring and weekly blood glucose curves. Diabetic remission occurred in all three cats between the second and third months of cabergoline treatment. At the time of writing, remission has persisted thus far (cat 1: 23 months; cat 2: 14 months; cat 3: 38 months). RELEVANCE AND NOVEL INFORMATION: To our knowledge, these are the first reported cases of diabetic remission in cats with hypersomatotropism after cabergoline treatment, despite previous reports of this being an ineffective treatment. Further work is indicated to determine why some cats do, and others do not, respond to this treatment.

Increased insulin-like growth factor 1 concentrations in a retrospective population of non-diabetic cats diagnosed with hypertrophic cardiomyopathy.

OBJECTIVES: The aim of the study was to document whether a proportion of non-diabetic cats with left ventricular hypertrophy (LVH) previously diagnosed with hypertrophic cardiomyopathy (HCM) have elevated circulating insulin-like growth factor 1 (IGF-1) concentrations. METHODS: A retrospective analysis of residual blood samples obtained at the time of echocardiographic diagnosis of HCM from a population of 60 non-diabetic cats were analysed for circulating IGF-1 concentrations using a validated radioimmunoassay and compared with a control group of 16 apparently healthy cats without LVH. Clinical and echocardiographic data for cats with an IGF-1 level >1000 ng/ml were compared with those with an IGF-1 level <800 ng/ml. RESULTS: In total, 6.7% (95% confidence interval 1.8-16.2%) of cats with HCM had an IGF-1 level >1000 ng/ml. The prevalence of an IGF-1 level >1000 ng/ml in the control group was zero. CONCLUSIONS AND RELEVANCE: A small proportion of non-diabetic cats previously diagnosed with HCM had an IGF-1 concentration at a level that has been associated with feline hypersomatotropism (fHS) in the diabetic cat population. Further prospective research is required to confirm or refute the presence of fHS in non-diabetic cats with LVH and increased IGF-1.

Pilot study assessing the use of cabergoline for the treatment of cats with hypersomatotropism and diabetes mellitus.

OBJECTIVES: An affordable and effective treatment is needed to manage feline hypersomatotropism. The aim of this study was to assess whether treatment with oral cabergoline for 90 days in cats with hypersomatotropism and diabetes mellitus improved diabetic and insulin-like growth factor 1 (IGF-1) control. METHODS: This was a prospective cohort non-blinded pilot study enrolling client-owned cats with spontaneously occurring diabetes mellitus and hypersomatotropism. Cats received oral cabergoline (5-10 µg/kg q24h) for 90 consecutive days. Serum IGF-1 and fructosamine concentrations were measured on days 1, 30 and 90. Quality of life was determined using the DIAQoL-pet questionnaire on days 1 and 90. RESULTS: Nine cats were enrolled and eight completed the study. There was no significant change in the following: IGF-1 (day 1 median 2001 ng/ml [range 890-2001 ng/ml]; day 30 median 2001 ng/ml [range 929-2001 ng/ml]; day 90 median 1828 ng/ml [range 1035-2001 ng/ml]; χ2(2) = 0.667, P = 0.805); fructosamine (day 1 median 499 µmol/l [range 330-887 µmol/l], day 30 median 551 µmol/l [range 288-722 µmol/l], day 90 median 503 [range 315-851 µmol/l]; χ2(2) = 0.581, P = 0.764); or DIAQoL-pet score (median on day 1 -2.79 [range -4.62 to -0.28], median on day 90 -3.24 [range -4.41 to -0.28]; P = 0.715). There was a significant change of insulin dose (χ2(2) = 8.667, P = 0.008) with cats receiving higher insulin doses at day 90 compared with day 1 (median on day 1 was 0.98 [range 0.63-1.49] and median on day 90 was 1.56 [range 0.49-2.55] units/kg q12h; P = 0.026). CONCLUSIONS AND RELEVANCE: Cabergoline did not improve diabetic control or normalise insulin-like growth factor concentration, or improve patient quality of life.

Anaesthetic management and complications during hypophysectomy in 37 cats with acromegaly.

OBJECTIVES: The aim of this study was to describe the anaesthetic management and perianaesthetic complications encountered during hypophysectomy surgery in acromegalic cats. We explored relationships between animal demographic data, the anaesthetic protocol used and presence of perioperative complications. METHODS: Cats having undergone hypophysectomy surgery for the treatment of feline acromegaly at a single veterinary referral hospital were identified from hospital records. The anaesthesia records and clinical notes of these animals were retrospectively reviewed. Descriptive statistics were produced and binary logistic regression run to assess for any relationship between patient factors, anaesthetic management and complications during the perioperative period. RESULTS: Perianaesthetic complications identified included hypothermia, hypotension, bradycardia and airway obstruction. Mortality at 24 h post-anaesthesia was 8%. The use of alpha (α)2 agonists was associated with a lower incidence of hypotension. Fentanyl infusion was associated with a higher incidence of airway obstruction compared with remifentanil. Subjectively assessed anaesthetic recovery quality had an association with the number of days spent in the intensive care ward postoperatively. CONCLUSIONS AND RELEVANCE: The anaesthetic management described seems effective for hypophysectomy surgery in cats. Intraoperative complications were common and, while not apparently associated with 24 h patient outcome, drugs and equipment to manage these complications should be available.

Diabetes mellitus remission in a cat with pituitary-dependent hyperadrenocorticism after trilostane treatment.

CASE SUMMARY: An 8-year-old male neutered Persian cat was presented with polyuria, polydipsia, polyphagia and muscle weakness associated with a 7 month history of diabetes mellitus (DM). The cat had initially been treated with neutral protamine Hagedorn (NPH) insulin 2 U q12h, followed by porcine lente insulin 2 U q12h and, most recently, 3 U glargine insulin q12h, without improvement of clinical signs. The cat also suffered from concurrent symmetrical bilateral alopecia of thorax and forelimbs, abdominal distension and lethargy. Hyperadrenocorticism (HAC), specifically pituitary-dependent HAC, was suspected and confirmed through abdominal ultrasonography demonstrating bilateral adrenal enlargement, and a low-dose dexamethasone suppression test using 0.1 mg/kg dexamethasone intravenously. Trilostane treatment (initially 10 mg/cat PO q24h then increased to 10 mg/cat PO q12h) was started and insulin sensitivity gradually improved, ultimately leading to diabetic remission after an increased in trilostane dose to 13mg/cat PO q12h, 14 months after the DM diagnosis and 7 months after the initiation of trilostane therapy. RELEVANCE AND NOVEL INFORMATION: DM in cats with HAC is a difficult combination of diseases to treat. To our knowledge this is the first reported case of diabetic remission in a feline patient with HAC as a result of treatment with trilostane. Further work should focus on whether fine-tuning of trilostane-treatment protocols in cats with concurrent DM and HAC could lead to a higher proportion of diabetic remissions in this patient group.

Acceptance of home blood glucose monitoring by owners of recently diagnosed diabetic cats and impact on quality of life changes in cat and owner.

Objectives This study aimed to evaluate the acceptance of home blood glucose monitoring (HBGM) by owners of recently diagnosed diabetic cats, and the impact of choosing HBGM on the quality of life (QoL) changes of cat and owner, in addition to glycaemic changes during 6 months of follow-up. Methods Owners of cats diagnosed with diabetes mellitus (DM) and treated with insulin for 6-20 weeks were divided into an HBGM group and a non-HBGM group, based on their ability and willingness to perform HBGM after a standardised instruction session. The HBGM acceptance level and reasons for acceptance failure were documented; a questionnaire evaluated owners' experiences. For the following 6 months, changes in QoL, measured using the validated DIAQoL-pet quantification tool, and changes in glycaemic control parameters (clinical signs, serum fructosamine, blood glucose curve average/minimal/maximal/pre-insulin blood glucose) were compared between HBGM and non-HBGM groups at months 1, 3 and 6, as well as within the groups between baseline and months 1, 3 and 6. Results Thirty-eight cats were enrolled; 28 (74%) entered the HBGM group. There was no significant difference between groups in overall DIAQoL-pet score or glycaemic control parameters at any time point apart from the maximal blood glucose at month 6 (lower in the HBGM group). However, the DIAQoL-pet score, including indicators of owner worry about DM, worry about hypoglycaemia and costs, as well as glycaemic parameters, improved at all time points within the HBGM group but not within the non-HBGM group. Remission occurred in 9/28 (32%) HBGM group cats and 1/10 (10%) non-HBGM group cats ( P = 0.236). Conclusions and relevance HBGM was adopted successfully by most diabetic cat owners. Despite the extra task, positive changes in QoL parameters occurred in the HBGM group and not in the non-HBGM group. Although no difference was found in glycaemic control between the HBGM and non-HBGM groups during the 6 months of follow-up, significant glycaemic improvements were documented in the HBGM group.

Prospective evaluation of a protocol for transitioning porcine lente insulin-treated diabetic cats to human recombinant protamine zinc insulin.

Objectives The objective was to evaluate a nadir-led protocol for transitioning porcine lente insulin suspension (PLIS)-treated diabetic cats onto human recombinant protamine zinc insulin (PZIR). Methods Recently diagnosed (<5 months) diabetic cats, treated with PLIS q12h for ⩾6 weeks, were recruited. Fructosamine, 24 h blood glucose curve (BGC), quality of life assessment (DIAQoL-pet score) and Diabetic Clinical Score (DCS) were assessed at enrolment (PLIS-treated) and 2, 4 and 12 weeks after transitioning to PZIR (starting dose 0.2-0.7 U/kg q12h). Short duration of insulin action was defined as <9 h. Linear mixed effects modelling assessed for change in fructosamine, mean blood glucose (MBG) during BGCs, DIAQoL-pet score, DCS and q12h insulin dose. McNemar's tests compared the proportion of cats with hypoglycaemia at week 0 (PLIS-treated) and week 4 (PZIR-treated). Results Twenty-two cats were recruited. Median PLIS dose at enrolment was 0.5 U/kg (interquartile range 0.3-0.7 U/kg) q12h, equalling median PZIR starting dose (0.5 U/kg; interquartile range 0.3-0.7 U/kg q12h). Transitioning was followed by significant decreases in fructosamine ( P = 0.00007), insulin dose ( P = 0.02), DCS ( P = 8.1 × 10-8) and DIAQoL-pet score ( P = 0.003), indicating improved quality of life. MBG did not alter significantly ( P = 0.1). Five cats (22.7%) achieved remission. Hypoglycaemia was recorded in 30/190 12 h BGCs (15.8%) and five cats experienced clinical hypoglycaemia. The proportion of cats with hypoglycaemia did not differ between PLIS (week 0) and PZIR (week 4) ( P = 1.0). Duration of action was analysed in 19 cats. Six cats (31.6%) showed short duration of action on PLIS, compared with two cats (10.5%) after 4 weeks on PZIR. All six cats with short PLIS duration showed duration of ⩾9 h on PZIR. Conclusions and relevance Used alongside a low-carbohydrate diet, transitioning to PZIR was associated with significantly improved clinical signs and quality of life, with some cats achieving remission. Transition to PZIR should be considered for cats with short duration of action on PLIS.