Long-term effects of intralymphatic immunotherapy (ILIT) on canine atopic dermatitis

The safety of rush immunotherapy in the management of canine atopic dermatitis-230 cases

BACKGROUND

The duration of the induction phase of allergen-specific immunotherapy conventionally is a period of several weeks, during which the volume of an allergen solution, administered by injection, is gradually increased until the maintenance dose is reached. In rush immunotherapy (RIT), the induction period is abbreviated to achieve a faster improvement in clinical signs of atopic dermatitis (AD) compared to conventional immunotherapy.

OBJECTIVE

The aim of this retrospective study was to evaluate the safety of RIT in 230 dogs with AD and report any adverse effects (AE).

ANIMALS

Two hundred thirty client-owned dogs.

MATERIALS AND METHODS

Medical records of dogs receiving RIT between 2012 and 2021 were analysed and observed AE were investigated. All dogs underwent RIT following a protocol of subcutaneous allergen extract injections, given hourly with an incrementally increasing volume from 0.1 to 1.0 mL.

RESULTS

Adverse effects were documented in 6 of 230 (2.6%) dogs. Five of these dogs (2.2%) showed mild gastrointestinal signs (1 of 5 vomiting, 4 of 5 diarrhoea) and one patient an increase in body temperature by 1.5°C. These occurred at different stages of the RIT protocol. All AE were graded as mild and self-limiting.

CONCLUSIONS AND CLINICAL RELEVANCE

Based on these data, supervised RIT in dogs appears to be a safe procedure to achieve the maintenance dose of allergen immunotherapy earlier with infrequent and mild AE.

Efficacy of short-term combination of intralymphatic allergen immunotherapy and lokivetmab treatment in canine atopic dermatitis: A double-blinded, controlled, randomised study

BACKGROUND

Allergen-specific immunotherapy (ASIT) is an effective therapy for canine atopic dermatitis (cAD). Intralymphatic immunotherapy (ILIT) is potentially beneficial in decreasing time to clinical effectiveness.

OBJECTIVE

To compare clinical efficacy of six monthly ILIT injections combined with three monthly injections of lokivetmab (LVM) with monthly LVM monotherapy at Day (D)168. To monitor dogs treated with ILIT for an additional six months of subcutaneous immunotherapy (SCIT).

ANIMALS

Thirty-six client-owned dogs with cAD.

MATERIALS AND METHODS

In this double-blinded, randomised study, dogs received either six monthly injections of ILIT combined with three monthly LVM injections (ILIT group) or six monthly LVM injections (LVM group). Monthly evaluations with pruritus Visual Analogue Scale (pVAS), Canine Atopic Dermatitis Extent and Severity Index, 4th iteration (CADESI-04) and medication scores (MS) were undertaken. Owners completed a Quality of Life (QoL) questionnaire. Treatment success was predefined as ≥50% reduction in pVAS and CADESI-04 score ≤ 10. After D168, the ILIT group continued with SCIT until subjective assessment at 12 months.

RESULTS

The treatment benchmark at D168 was achieved by 11.1% of the ILIT group and 11.8% of LVM group. A significant decrease in mean pVAS and CADESI scores was observed in both groups (p < 0.001). The ILIT group had a trend towards higher MS compared to LVM. QoL was better in LVM (p = 0.01). At 12 months subjective good-to-excellent response in 77.8% of dogs in the ILIT/SCIT group was seen.

CONCLUSION AND CLINICAL RELEVANCE

The efficacy of this ILIT protocol was comparable with LVM monotherapy at six months. When ILIT was continued with SCIT, a favourable response was seen.

A randomised, double-blinded comparison between subcutaneous rush and intralympathic allergen immunotherapy induction in atopic dogs

BACKGROUND

Atopic dermatitis (AD) is one of the most common skin diseases in small animal practice. Allergen immunotherapy (AIT) is the only curative treatment for the disease, and oral, subcutaneous and intralymphatic administration of allergens are commonly employed.

OBJECTIVES

To compare the efficacy of AIT following an induction phase with intralymphatic injections (ILIT) or rush immunotherapy (RIT).

ANIMALS

Fifty privately owned dogs with AD.

MATERIALS AND METHODS

In a double-blinded study, dogs were randomly assigned to either four monthly ILIT of allergen extract or RIT with five injections administered subcutaneously at hourly intervals on the first day. They were assessed by validated scores; Canine Atopic Dermatitis Lesion Index (CADLI) and pruritus Visual Analog Scale (PVAS) at the beginning of the study and after 1, 3, 6 and 12 months. The latter were performed daily for 7 days before each revisit. Medication scores and a total clinical score were calculated and compared between each group and time point.

RESULTS

There was no significant difference in CADLI and PVAS scores, or CADLI and medication scores between groups at any of the time points. A significant improvement with both ILIT and RIT was seen in total and pruritus scores, respectively. An owner global assessment of good-to-excellent treatment efficacy was seen in 40% of the dogs; total scores improved by 27% and 35% in the RIT and ILIT group, respectively. Adverse effects were not seen.

CONCLUSIONS AND CLINICAL RELEVANCE

Induction of AIT can be conducted either as RIT or ILIT with no loss in efficacy.

Quality of Life of Allergic Dogs Treated with Allergen-Specific Immunotherapy-A Retrospective Study

BACKGROUND

The quality of life (QoL) of dogs with canine atopic dermatitis (CAD) treated with allergen-specific immunotherapy (ASIT) was studied to determine whether the QoL of dogs treated with ASIT (AG) improved compared with dogs not treated with ASIT (CG).

METHODS

The power of the study was calculated in advance assuming that the AG would assess QoL 20% better than the CG. The CG consisted of 21 dogs with CAD and the AG of 46 dogs with CAD. Validated QoL1 (pre-treatment) and QoL2 (post-treatment) questionnaires were emailed to owners.

RESULTS

AG dogs were significantly less disturbed during mealtimes (i.e., had better appetites and scratched less during mealtimes) and caused significantly less physical discomfort to their owners (due to unpleasant odor, the impression of a dirty apartment) than CG dogs. Owners of dogs treated with ASIT were able to significantly improve their daily activities (leisure, vacation, walks, work, hunting), significantly reduce their expenses (treatment costs, veterinary costs), feel significantly less emotional distress (less guilt, powerlessness, sadness, regret, fear, anger, disgust, rage, frustration), and experience less influence on relationships with family members and friends compared to owners of dogs not treated with ASIT.

CONCLUSIONS

According to our results, the quality of life of dogs treated with ASIT and their owners seemed to improve significantly.

Strengthening the case for intralymphatic immunotherapy

PURPOSE OF REVIEW

Intralymphatic immunotherapy (ILIT) is a promising novel method of immunotherapy, that is short and convenient, and may be very effective. Results have been varied, and efforts to unravel the real value of the treatment are ongoing. Methods used to assess the effect in clinical trials have been so varied that it is difficult to compare studies with each other.

RECENT FINDINGS

Some advances have been made; the importance of injecting into the lymph node has been illustrated, and treatment with a range of medicines has proven to be successful. In meta-analyses the treatment has been shown to have no serious side effects and to be an effective short term desensitizing agent. Now it remains to be shown that ILIT also has long-term effects of tolerance. Preliminary data suggest that there is a long-term effect.

SUMMARY

Injecting allergen directly into a lymph node strengthens the protective immune response. ILIT is safe and induces desensitization and very likely also induces tolerance. Compliance will improve compared with other treatment forms. If ILIT holds its promise, it will become an attractive option for patients with allergy.

Development and validation of an owner-assessed Visual Analog Scale for feline pruritus severity scoring (VAScat)

BACKGROUND

Assessment of the severity of pruritus is difficult in cats, because they manifest discomfort by increased licking, increased scratching or both.

HYPOTHESIS/OBJECTIVES

Our objective was to develop and validate a feline-specific pruritus scale (VAScat).

METHODS

The scale was designed as a double Visual Analog Scale (VAS), one VAS for licking and one for scratching, with severity and behavioural descriptors. The highest score (VAS-max) on either VAS was taken as the pruritus score for each cat. Owners of 153 cats with skin diseases and of 108 healthy cats scored their pet's pruritus using the VAScat. Ninety-six of 153 cats with skin diseases also were re-evaluated after four to eight weeks of treatment.

RESULTS

Pearson's correlation value between VAS-licking and VAS-scratching scores was r = 0.26 (p < 0.01), and Cronbach's alpha was 0.41. Both indexes indicated that the two scales measure different manifestations of pruritus and supported the use of a dual assessing system. Comparison with a numerical pruritus severity scale (0, absent; 1, mild; 2, moderate; 3, severe) suggested that VAS-licking and VAS-scratching scales taken alone are unsuitable for measuring absent to mild pruritus (grades 0-1), while VAS-max is (p = 0.001). VAS-licking, VAS-scratching and VAS-max all were suitable to assess higher levels of pruritus (grades 2-3, p < 0.01). The VAScat was able to measure pruritus improvement following therapy, as post-treatment scores were significantly decreased compared to pre-treatment ones (p < 0.0001).

CONCLUSIONS AND CLINICAL IMPORTANCE

The VAScat proved to be a useful tool to assess pruritus in cats and for monitoring the response to treatment for pruritus.

Shortened immunotherapy dose-escalation saves time, but is it safe? A case-control study comparing the rates of adverse reactions between conventional and fast-escalation subcutaneous immunotherapy protocols during the induction phase

BACKGROUND

Allergen immunotherapy (AIT) is the only intervention believed to change the course of atopic diseases. As dogs appear to have fewer severe adverse events (AEs) compared to people receiving AIT, a prolonged dose-escalation induction phase might not be needed.

OBJECTIVES

To report the incidence and characteristics of AEs induced by a fast-escalation subcutaneous immunotherapy (f-SCIT) protocol compared to a conventional (c-SCIT) regimen.

ANIMALS

One hundred dogs treated with either f- SCIT (Centre 1, 50 dogs) or c-SCIT (Centre 2, 50 dogs).

METHODS AND MATERIALS

A case-control study retrospectively evaluating AEs during the induction of AIT. We determined the incidence and type of AEs in each SCIT group; we also assessed factors such as self-limitation and the need for AE-associated protocol changes.

RESULTS

Twelve of 100 dogs (12%) developed a SCIT-attributable AE during the induction phase, with one dog having a local and 11 having systemic reactions (nine Grade I, two Grade II, none of grades III or IV). Dogs treated with the f-SCIT had a significantly higher rate of AEs (11 of 50; 22%) compared to those receiving the c-SCIT (one of 50; 2%). Most of the AEs (10 of 11; 91%) in the f-SCIT group were mild and self-limiting.

CONCLUSIONS AND CLINICAL IMPORTANCE

The induction phase of f-SCIT is simpler, and the maintenance phase is reached faster than that of the c-SCIT. Despite its higher rate of AEs than with the c-SCIT regimen, the majority of f-SCIT-associated AEs were mild and self-limiting. Whether or not this f-SCIT protocol leads to a faster time-to-efficacy needs to be determined.

A comparative study of subcutaneous, intralymphatic and sublingual immunotherapy for the long-term control of dogs with nonseasonal atopic dermatitis

BACKGROUND

Allergen-specific immunotherapy (ASIT) is the only causative treatment of canine atopic dermatitis (cAD). Different routes for administration of ASIT have been used; however, comparative studies are lacking.

HYPOTHESIS/OBJECTIVES

The present study compared the efficacy and safety of subcutaneous (SCIT), intralymphatic (ILIT) and sublingual (SLIT) immunotherapy.

ANIMALS

30 atopic dogs were included and allocation to three groups (SCIT, n = 8; ILIT, n = 12; SLIT, n = 10) was determined by the owners.

METHODS AND MATERIALS

ASIT was administered using routine protocols. The pruritus Visual Analog Scale (PVAS), canine atopic dermatitis extent and severity index (CADESI), concurrent medications and adverse events were recorded initially and one, three, six and 12 months later. The main outcome measure was return to a normal status, which included CADESI <12, PVAS <2.5 and medication score <10.

RESULTS

Drop-outs were distributed evenly and 23 dogs finished the study (SCIT, n = 6; ILIT, n = 10; SLIT, n = 7). Adverse reactions to treatment were rare. At the start of the study, the three groups were homogeneous with respect to clinical signs and concurrent medications. After 12 months of ASIT, the CADESI and PVAS had decreased with a stable medication score in the ILIT and SCIT groups (P < 0.05), while all three scores had increased in the SLIT group. Return to normal state was achieved in one of six (17%) dogs receiving SCIT, in six of 10 (60%) dogs receiving ILIT and in one of seven (14%) dogs receiving SLIT.

CONCLUSIONS AND CLINICAL IMPORTANCE

These findings suggest that SCIT and ILIT improved clinical signs of cAD, whereas ILIT had a much higher return to normal rate.

Sterile granulomatous dermatitis and lymphadenitis (juvenile cellulitis) in adult dogs: a retrospective analysis of 90 cases (2004-2018)

BACKGROUND

It has long been speculated that sterile granulomatous dermatitis and lymphadenitis (SGDL) occurs in adult dogs. However, only three published case reports exist.

HYPOTHESIS/OBJECTIVES

To describe clinical presentation, identify breed predispositions, and assess treatment and outcomes of adult dogs with the histopathological diagnosis of SGDL.

ANIMALS

Included are 90 dogs with biopsies submitted to a veterinary teaching hospital with a histopathological diagnosis consistent with SGDL, from 2004 to 2018, of which 35 had medical records available for review.

METHODS

Data were analysed retrospectively from histopathology submission forms, medical records, surveys and telephone calls. Scoring systems were created to aid statistical analysis of outcomes.

RESULTS

Havanese dog (P < 0.0001), Australian shepherd dog (P < 0.0001), Irish setter (P < 0.0001), Dachshund (P = 0.0002), bichon frise (P = 0.0003) and Maltese dog (P = 0.004) were significantly over-represented breeds. The median age at onset was 1,292 days (3.54 years). Dogs up to five years of age were significantly over-represented (P < 0.01). Of 35 dogs with medical records available for review, the median treatment duration was 60 days and the median time to remission 28 days. Remission status was not established for five dogs but the remaining 30 dogs reached remission. Nineteen dogs remained in complete remission. Recrudescence occurred in 11 dogs (median follow-up 60 days).

CONCLUSIONS AND CLINICAL IMPORTANCE

This study shows a close parallel in clinical appearance, histopathological results and clinical behaviour, of both adult and juvenile onset SGDL; therefore, SGDL should be considered as a differential diagnosis for dogs of all ages.

Canine ischaemic dermatopathy: a retrospective study of 177 cases (2005-2016)

BACKGROUND

Ischaemic dermatopathy encompasses a poorly understood subset of canine diseases that share similar clinical and histological features. Very little information is currently available regarding population characteristics, progression and outcome.

HYPOTHESIS/OBJECTIVES

This study aimed to describe the clinical features and therapeutic outcomes of ischaemia dermatopathy, excluding familial dermatomyositis, using cases diagnosed by histopathological analysis.

ANIMALS

One hundred and seventy-seven cases submitted for histopathological analysis between 2005 and 2016 met inclusion criteria, of which 93 had complete medical records available.

METHODS AND MATERIALS

Both records and pointed surveys were used to retrieve information. Scoring systems were created to subjectively evaluate clinical outcomes and likelihood of a vaccine association.

RESULTS

Of 177 cases, toy and miniature poodles, Chihuahuas, Maltese, Yorkshire terriers and Jack Russell terriers were significantly over-represented (P < 0.001). Of the 93 cases for which historical data were obtained, median age at skin biopsy was five years (0.42-13 years) and median body weight was 7.3 kg (range 1.32-50.3 kg). The condition in 45 dogs (48.3%) was found likely to be associated with vaccination. Younger ages (P = 0.011) and higher body weights (P = 0.003) were positively correlated with greater likelihood of vaccination. Body weight <10 kg (P = 0.0045) and older ages (P = 0.0048) were significantly associated with worse outcomes.

CONCLUSIONS AND CLINICAL IMPORTANCE

This study provides support for breed predispositions and identifies potential prognostic factors. Importantly, over half of the cases were considered unlikely to be vaccine-associated, demonstrating the need to investigate other underlying causes of this condition.

Atopic dermatitis in cats and dogs: a difficult disease for animals and owners

The purpose of this review article is to give an overview of atopic dermatitis in companion animals and of recent developments including knowledge on immunological background, novel treatment options and difficulties in disease management. The prevalence of hypersensitivities seems to be increasing. The pathogenetic mechanisms are not fully understood, yet multiple gene abnormalities and altered immunological processes are involved. In dogs and cats, the diagnosis of atopic dermatitis is based on history, clinical examination and exclusion of other differential diagnoses. Intradermal testing or testing for serum allergen-specific Immunoglobulin E is only used to identify allergens for inclusion in the extract for allergen immunotherapy. Symptomatic therapy includes glucocorticoids, ciclosporin, essential fatty acids and antihistamines. A selective janus kinase 1 inhibitor and a caninized monoclonal interleukin-31 antibody are the newest options for symptomatic treatment, although longterm effects still need to be assessed. The chronic and often severe nature of the disease, the costly diagnostic workup, frequent clinical flares and lifelong treatment are challenging for owners, pets and veterinarians. Patience and excellent communication skills are needed to achieve a good owner compliance and satisfactory clinical outcome for the animal.

Allergen immunotherapy in people, dogs, cats and horses - differences, similarities and research needs

In human patients with seasonal allergic rhinoconjunctivitis sensitized to grass pollen, the first successful allergen immunotherapy (AIT) was reported in 1911. Today, immunotherapy is an accepted treatment for allergic asthma, allergic rhinitis and hypersensitivities to insect venom. AIT is also used for atopic dermatitis and recently for food allergy. Subcutaneous, epicutaneous, intralymphatic, oral and sublingual protocols of AIT exist. In animals, most data are available in dogs where subcutaneous AIT is an accepted treatment for atopic dermatitis. Initiating a regulatory response and a production of "blocking" IgG antibodies with AIT are similar mechanisms in human beings and dogs with allergic diseases. Although subcutaneous immunotherapy is used for atopic dermatitis in cats, data for its efficacy are sparse. There is some evidence for successful treatment of feline asthma with AIT. In horses, most studies evaluate the effect of AIT on insect hypersensitivity with conflicting results although promising pilot studies have demonstrated the prophylaxis of insect hypersensitivity with recombinant antigens of biting midges (Culicoides spp.). Optimizing AIT using allergoids, peptide immunotherapy, recombinant allergens and new adjuvants with the different administration types of allergen extracts will further improve compliance and efficacy of this proven treatment modality.