Multiple Pyoderma Gangrenosum Overlying AV Fistula Treated With Colchicine: A Case Report.

Rationale: Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis which gives rise to painful ulcers. Pyoderma gangrenosum can be triggered by trauma, a phenomenon called pathergy. Here, we report the first case of PG arising from pathergy due to needle insertion overlying an arteriovenous fistula (AVF). This case report seeks to inform nephrologists about PG, this yet unreported presentation, and management in the context of hemodialysis. Presenting concerns: A 69-year-old woman presented to dermatology clinic for erythemato-violaceous plaques with central ulceration at the site of needle insertion overlying her AVF. The patient was known for chronic renal insufficiency secondary to C3 glomerulonephritis, for which she received hemodialysis. After an accidental burn which lead to appearance of a painful ulcer, following each needle insertion for hemodialysis, she would develop an erythematous papule that progressed to a painful ulcer with erythematous-violaceous borders. Diagnosis: Pyoderma gangrenosum was clinically diagnosed and both clinical and paraclinical evaluation did not reveal any secondary cause of PG. Intervention: Dialysis via AVF was suspended due to the risk of triggering more PG and was temporarily pursued by central venous catheter. The patient was initially treated with prednisone and topical corticosteroids. Furthermore, owing to the high recurrence rate of PG, colchicine was initiated in prevention to avoid resorting to immunosuppressive or long-term corticotherapy. Outcomes: The patient's lesions improved on prednisone, which was then tapered over 1 month. Following prednisone taper and continuing improvement of PG on colchicine and topical corticosteroids alone, the decision was taken to recommence dialysis via AVF after performing a negative pathergy test. Topical corticosteroids were ceased due to the risk of cutaneous atrophy and were replaced by pimecrolimus ointment. The patient has continued dialysis via AVF ever since, without recurrence. Novel Finding: This is the first case reported of PG arising from pathergy due to needle insertion overlying an AVF. Colchicine may be a safe and effective therapy for long-term treatment of PG in the context of hemodialysis.

Contexte: Le Pyoderma gangrenosum (PG) est une dermatose neutrophilique rare qui provoque des ulcères douloureux. Le PG peut être déclenché par un traumatisme, un phénomène appelé pathergie. Nous rapportons ici le premier cas de PG résultant d'une pathergie au site d'insertion de l'aiguille recouvrant une fistule artérioveineuse. Ce rapport de cas vise à informer les néphrologues sur le PG, sur cette présentation non encore rapportée et sur sa prise en charge dans le contexte de l'hémodialyse. Présentation du cas: Une femme âgée de 69 ans s'étant présentée à une clinique de dermatologie pour soigner des plaques érythémateuses violacées avec ulcération centrale au site d'insertion de l'aiguille recouvrant sa fistule artérioveineuse (FAV). La patiente était connue pour une insuffisance rénale chronique secondaire à une glomérulonéphrite à C3, pour laquelle elle recevait des traitements d'hémodialyse. À la suite d'une brûlure accidentelle ayant entraîné l'apparition d'un ulcère douloureux, la patiente développait une papule érythémateuse qui évoluait vers un ulcère douloureux aux bords érythémateux violacés après chaque insertion d'aiguille pour l'hémodialyse. Diagnostic: Le Pyoderma gangrenosum a été diagnostiqué cliniquement et l'évaluation, tant clinique que paraclinique, n'a révélé aucune cause secondaire de PG. Intervention: En raison du risque accru de déclenchement de PG, la dialyse par la FAV a été suspendue et remplacée temporairement par la dialyse par cathéter veineux central. La patiente a d'abord reçu un traitement de prednisone et de corticostéroïdes topiques. En raison du taux élevé de récidive de PG, un traitement préventif à la colchicine a été initié pour éviter le recours à une corticothérapie immunosuppressive ou à long terme. Résultats: Les lésions de la patiente se sont améliorées avec le traitement à la prednisone, celui-ci a ensuite été réduit progressivement sur une période d'un mois. Après la réduction progressive de la prednisone et en raison de l'amélioration continue du PG avec le traitement par colchicine et corticostéroïdes topiques seulement, la décision a été prise de recommencer la dialyse par la FAV après un test de pathergie négatif. Un risque d'atrophie cutanée a justifié l'arrêt des corticostéroïdes topiques qui ont été remplacés par une pommade de pimecrolimus. Depuis, la patiente a poursuivi sa dialyse par FAV, sans récidive. Principales observations: Il s'agit du premier cas signalé de PG résultant d'une pathergie au site d'insertion de l'aiguille recouvrant une fistule artérioveineuse. La colchicine peut s'avérer un traitement sûr et efficace pour le traitement à long terme du PG dans le contexte de l'hémodialyse.

Assessment and comparison of probability scores to predict giant cell arteritis.

INTRODUCTION/OBJECTIVES: To assess and compare the performance of the giant cell arteritis probability score (GCAPS), Ing score, Bhavsar-Khalidi score (BK score), color Doppler ultrasound (CDUS) halo count, and halo score, to predict a final diagnosis of giant cell arteritis (GCA). METHOD: A prospective cohort study was conducted from April to December 2021. Patients with suspected new-onset GCA referred to our quaternary CDUS clinic were included. Data required to calculate each clinical and CDUS probability score was systematically collected at the initial visit. Final diagnosis of GCA was confirmed clinically 6 months after the initial visit, by two blinded vasculitis specialists. Diagnostic accuracy and receiver operator characteristic (ROC) curves for each clinical and CDUS prediction scores were assessed. RESULTS: Two hundred patients with suspected new-onset GCA were included: 58 with confirmed GCA and 142 without GCA. All patients with GCA satisfied the 2022 ACR/EULAR classification criteria. A total of 5/15 patients with GCA had a positive temporal artery biopsy. For clinical probability scores, the GCAPS showed the best sensitivity (Se, 0.983), whereas the BK score showed the best specificity (Sp, 0.711). As for CDUS, a halo count of 1 or more was found to have a Se of 0.966 and a Sp of 0.979. Combining concordant results of clinical and CDUS prediction scores showed excellent performance in predicting a final diagnosis of GCA. CONCLUSION: Using a combination of clinical score and CDUS halo count provided an accurate GCA prediction method which should be used in the setting of GCA Fast-Track clinics. Key Points • In this prospective cohort of participants with suspected GCA, 3 clinical prediction tools and 2 ultrasound scores were compared head-to-head to predict a final diagnosis of GCA. • For clinical prediction tools, the giant cell arteritis probability score (GCAPS) had the highest sensitivity, whereas the Bhavsar-Khalidi score (BK score) had the highest specificity. • Ultrasound halo count was both sensitive and specific in predicting GCA. • Combination of a clinical prediction tool such as the GCAPS, with ultrasound halo count, provides an accurate method to predict GCA.

Optic nerve sheath measurement to monitor disease activity in giant cell arteritis: a pilot study.

INTRODUCTION/OBJECTIVES: Optic nerve sheath (ONS) enhancement using magnetic resonance imaging of the orbits was observed in patients with giant cell arteritis (GCA). We previously showed that ONS diameter (ONSD) by bedside ultrasound is increased in patient with active GCA. This study aims to assess whether ONSD decreases with clinical remission in patients with GCA. METHODS: A prospective cohort study was conducted from June 2022 to January 2023. Patients who had an optic nerve ultrasound at GCA diagnosis as part of a previous crosssectional study were eligible. Optic nerve ultrasound was performed by the same investigator at diagnosis and month 3. ONSD (includes the optic nerve and its sheath) and optic nerve diameter (OND) were measured. Descriptive statistics for baseline characteristics and paired sample t-test were performed to assess the mean difference in OND and ONSD between diagnosis and month 3. RESULTS: Nine patients with GCA were included. The median age at disease onset was 79 years (interquartile range (IQR) of 79-82 years), and 7 patients were males. All patients were in clinical remission at month 3 on prednisone (median dose of 15 mg/day, IQR of 10-25 mg). The mean ONSD was lower at month 3 (3.76 mm) compared to baseline (5.98 mm), with a paired mean difference of 2.22 mm (95% CI 1.41-3.03 mm, p < 0.001). As anticipated, OND measurements did not vary between diagnosis and month 3. CONCLUSION: ONSD on ultrasound improves after 3 months of therapy in patients with GCA. A longer prospective study is required to determine if ONSD is useful to assess disease activity in GCA. Key Points • ONS ultrasound can identify patients with active GCA. • The ONSD on ultrasound is dynamic and improved after 3 months of GCA therapy. • ONS ultrasound may be useful to monitor disease activity in GCA.

Optic Nerve Sheath Measurement on Ultrasound: A Novel Diagnostic Test for Giant Cell Arteritis.

OBJECTIVE: Optic nerve sheath enhancement on magnetic resonance imaging has been reported in patients with giant cell arteritis (GCA), with or without visual manifestations. Whether similar findings can be documented on ultrasound is unknown. Optic nerve ultrasound is a point-of-care, easy to learn, rapid, and noninvasive technique. This study aims to investigate whether optic nerve sheath diameter (ONSD) measured on ultrasound is useful in the diagnosis of active, new-onset GCA. METHODS: A single-center, diagnostic accuracy study was performed from June to November 2022 on consecutive eligible patients referred for suspected GCA. Optic nerve ultrasound was performed on both eyes. The ONSD (includes the optic nerve and its sheath) and optic nerve diameter (OND) were measured 3 mm behind the ocular globe. The presence or absence of GCA was confirmed clinically 6 months later. Multivariable linear regression, adjusting for age and sex, was used to determine the association between optic nerve ultrasound measures and final GCA diagnosis. RESULTS: Thirty participants were enrolled, including nine participants with a final diagnosis of GCA. Mean ± SD ONSD was 5.98 ± 1.17 mm in patients with GCA and 4.02 ± 0.99 mm in patients without GCA. Mean ONSD was greater by 1.26 mm in patients with GCA (95% confidence interval 0.30-2.21 mm, P = 0.01) compared with those without GCA, adjusting for age and sex. Mean ± SD OND was 2.97 ± 0.46 mm in patients with GCA and 2.47 ± 0.58 mm in patients without GCA. There was no evidence of an association between GCA diagnosis and OND. CONCLUSION: Patients with GCA had a significantly greater ONSD on ultrasound than patients without GCA. Optic nerve ultrasound may represent a novel, rapid, bedside diagnostic test for GCA. A large prospective study is required to confirm these findings and evaluate whether ONSD can be used as a disease activity biomarker in GCA.

Comparison of Interstitial Lung Disease Between Antineutrophil Cytoplasmic Antibodies Positive and Negative Patients: A Retrospective Cohort Study.

OBJECTIVE: Positive antineutrophil cytoplasmic antibodies (ANCAs) may occur in the setting of interstitial lung disease (ILD), with or without ANCA-associated vasculitis (AAV). We aim to compare the characteristics and clinical course of patients with ILD and positive ANCA (ANCA-ILD) to those with negative ANCA. METHODS: We performed a single-center retrospective cohort study from 2018 to 2021. All patients with ILD and ANCA testing were included. Patient characteristics (symptoms, dyspnea scale, and systemic AAV), test results (pulmonary high-resolution computed tomography and pulmonary function tests), and adverse events were collected from electronic medical records. Descriptive statistics and the Fisher exact test were used to compare the outcomes of patients with ANCA-ILD to those with ILD and negative ANCA. RESULTS: A total of 265 patients with ILD were included. The mean follow-up duration was 69.3 months, 26 patients (9.8%) were ANCA positive, and 69.2% of those with ANCA-ILD had another autoantibody. AAV occurred in 17 patients (65.4%) with ANCA-ILD. In 29.4% of patients, AAV developed following ILD diagnosis. Usual interstitial pneumonia was the most common radiologic pattern in patients with ANCA-ILD. There was no association between ANCA status and the evolution of dyspnea, diffusing capacity of the lungs for carbon monoxide, and lung imaging. Forced vital capacity improved over time in 42% of patients with ANCA-ILD and in 17% of patients with negative ANCA (P = 0.006). Hospitalization occurred in 46.2% of patients with ANCA-ILD and in 21.8% of patients with negative ANCA (P = 0.006). Both groups had similar mortality rates. CONCLUSION: Routine ANCA testing should be considered in patients with ILD. Patients with ANCA-ILD are at risk for AAV. More research is required to better understand and manage patients with ANCA-ILD.

Colour Doppler ultrasound and the giant cell arteritis probability score for the diagnosis of giant cell arteritis: a Canadian single-centre experience.

OBJECTIVES: The aim was to compare the accuracy of colour Doppler ultrasonography (CDUS) and temporal artery biopsy (TAB) to establish the final diagnosis of GCA and to determine how the GCA probability score (GCAPS) performs as a risk stratification tool. METHODS: Descriptive statistics were performed on a retrospective cohort of patients referred to our vasculitis referral centre between 1 July 2017 and 1 October 2020 for suspected GCA. CDUS, TAB, centre-specific TAB (vasculitis centre vs referring hospitals) and GCAPS were compared against the final diagnosis of GCA as determined by a GCA expert; CDUS was also compared with TAB results. RESULTS: Data from 198 patients were included: 60 patients with GCA and 138 patients without GCA. Sixty-two patients had a TAB. Using the final diagnosis by a GCA expert as a reference, the sensitivity, specificity, positive predictive value and negative predictive value were 93.3%, 98.5%, 96.6% and 97.1% for CDUS and 69.2%, 100%, 100% and 81.8% for TAB, respectively. The false-negative rate was 6.7% for CDUS and 30.8% for TAB. False-negative TAB mostly occurred when performed in referring hospitals (57.1%) as opposed to our vasculitis centre (21.1%). With a cut-off at 9.5 points, sensitivity for GCAPS was 98.3% and specificity 74.3%. CONCLUSION: CDUS of the temporal and axillary arteries showed a high sensitivity and specificity and helped to diagnose GCA in patients with negative TAB. We validated that GCAPS is a useful clinical tool, with a score of <9.5 making the diagnosis of GCA improbable.

Henoch-Schonlein purpura in pregnancy: A case report.

Henoch-Schonlein purpura is a relatively common pediatric vasculitis. Very few cases of Henoch-Schonlein purpura during pregnancy have been described. Henoch-Schonlein purpura is variable in its presentation, from completely benign to possibly catastrophic complications. This rarely encountered condition in adults can also be a recurrence of a previous childhood disease. We present a case of a pregnant 40-year-old woman with Henoch-Schonlein purpura, resulting in a viable birth with no fetal complications. Her presentation is discussed in detail and a general presentation of Henoch-Schonlein purpura is explored, with particular attention to its rare onset during pregnancy.