Transient Telangiectatic Purpura: A Rare Post-operative Phenomenon.

Axillary lymph node dissection (ALND) is a surgical procedure for malignant disease with well known complications, that is less well known is its association with a painless dermatomal rash formally known as transient telangiectatic purpura. This is a case report describing a case of transient telangiectatic purpura, describing its natural history and inferring on its pathophysiology.

An Unusual Complication of Lisinopril: A Report of Iatrogenic Henoch-Schönlein Purpura.

Henoch-Schönlein purpura (HSP), also known as IgA vasculitis, is a hypersensitivity vasculitis characterized by palpable purpuric lesions associated with polyarthralgia, abdominal discomfort, and renal involvement. We present the case of a 41-year-old man who was admitted to the emergency department due to generalized purpuric lesions and abdominal pain. During the complementary study, there was no evidence of thrombocytopenia or coagulopathy but confirmed microscopic haematuria. The diagnosis of HSP was supported by the presence of leukocytoclastic vasculitis with perivascular IgA deposits in the skin biopsy. After excluding infectious, autoimmune, and neoplastic pathologies, the possibility of HSP associated with taking lisinopril, which had been recently initiated after hospitalization for acute heart failure, was assumed. Angiotensin-converting enzyme (ACE) inhibitor suspension and treatment with systemic corticosteroids lead to significant clinical regression, supporting our suspicion.

Severe Immune Thrombocytopenic Purpura in a Pediatric Patient With Fanconi Anemia: A Case Report.

Fanconi anemia (FA) is a rare inherited disorder characterized by progressive bone marrow failure, chromosomal instability, and an increased predisposition to malignancies. Autoimmune manifestations are uncommon in FA, with immune thrombocytopenic purpura (ITP) being a particularly rare presentation. ITP is an autoimmune disorder marked by immune-mediated platelet destruction, leading to severe thrombocytopenia and an increased risk of bleeding. This case report presents a pediatric patient with FA and severe ITP, illustrating the clinical challenges of managing autoimmune complications in the context of FA. This case report describes the case of a six-year-old boy with known FA who presented with a three-day history of spontaneous bruising, petechiae, and epistaxis. He had severe thrombocytopenia (platelet count: 8,000/µL) without other significant cytopenias. The initial workup excluded viral infections and other secondary causes, leading to the diagnosis of ITP. The patient was treated with intravenous immunoglobulin (IVIG) and corticosteroids, resulting in a transient improvement. However, his platelet counts declined, prompting treatment with rituximab, which achieved a sustained response. He was discharged after four weeks of rituximab therapy and remained stable at follow-up with a platelet count of 100,000/µL. This case highlights the rare occurrence of ITP in FA and the successful use of rituximab for refractory thrombocytopenia. The findings suggest a need for ongoing research into the mechanisms of immune dysregulation in FA and the development of optimized therapeutic strategies for managing autoimmune manifestations in this complex patient population.

A Rare Intersection: Managing Thrombotic Thrombocytopenic Purpura in the Context of Dengue Fever.

Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening condition that can lead to severe morbidity and mortality if untreated. This case report discusses a 31-year-old male with dengue fever who developed TTP, resulting in fatality despite timely diagnosis and comprehensive treatment. The patient presented with worsening symptoms, including body aches, gastrointestinal bleeding, and neurological issues. Initial treatment focused on managing dengue hemorrhagic fever, but TTP was later suspected, leading to the cessation of platelet transfusions and initiation of plasma exchange, steroids, and rituximab. Despite these efforts, the patient's condition deteriorated. This case underscores the challenges in managing TTP, especially when triggered by infections like dengue. The use of the PLASMIC score can be highly effective in suspecting TTP in these patients, allowing for the initiation of early management. While standard treatments include plasma exchange and immunosuppressive therapy, emerging treatments such as caplacizumab and the potential use of splenectomy may offer hope for better outcomes in the future.

A clinical case of pityriasis lichenoides chronica presenting with palpable purpura after streptococcal infection.

Pityriasis lichenoides is a rare inflammatory skin condition presenting with diffuse red-brown papules with evolution polymorphism and mica-like crust on older skin lesions. We present a 60-year-old female patient with pityriasis lichenoides chronica that manifested ten days after streptococcal pharyngitis. Initially, palpable purpura appeared on the lower extremities and later, erythematous-squamous papules and plaques appeared at the site of the palpable purpura and on the upper limbs and trunk. The patient had no history of hematological malignancy, viral hepatitis, kidney involvement, systemic rheumatic disease, or ANCA-associated vasculitis. After administration of methylprednisolone 20 mg for one month and an antimalarial agent (hydroxychloroquine 200 mg, 1 tablet bid) for three months, the skin lesions subsided without recurrence.

Rare Superior Mesenteric Artery Syndrome in an Eight-Year-Old Girl With Henoch-Schönlein Purpura: A Case Report.

Henoch-Schönlein purpura (HSP) is a systemic vasculitis characterized by palpable purpura, arthralgia or arthritis, GI symptoms, and renal involvement. Superior mesenteric artery (SMA) syndrome, a rare condition, occurs when the third part of the duodenum is compressed between the aorta and the SMA, leading to upper intestinal obstruction. This case report describes the clinical presentation, diagnostic process, and management of an eight-year-old girl with HSP complicated by SMA syndrome. The patient initially presented with abdominal pain and vomiting, eventually developing the characteristic rash of HSP. While initial management was supportive, her condition deteriorated. Treatment with intravenous methylprednisolone resulted in significant symptom improvement and resolution of both SMA syndrome and HSP manifestations. This case highlights the need to recognize SMA syndrome as a potential complication of HSP and demonstrates the effectiveness of steroid therapy in managing this condition. Further research is needed to develop comprehensive treatment guidelines for HSP patients with SMA syndrome.

Long-term safety and effectiveness of romiplostim for chronic idiopathic thrombocytopenic purpura in real-world settings.

Idiopathic thrombocytopenic purpura (ITP), an autoimmune hematologic disorder characterized by severe platelet count reduction, can be treated with romiplostim. However, post-marketing safety and effectiveness data for romiplostim in Japan are scarce. This prospective, observational, post-marketing Specified Use-Results Survey evaluated the real-world safety and effectiveness of romiplostim for 2 years. All patients treated with romiplostim during the survey period were eligible. Of the 1622 patients in the safety analysis set, 94.08% (1526/1622) had chronic ITP. The mean single dose of romiplostim was stable after 12 weeks and remained < 6 µg/kg in approximately 70% of patients until 104 weeks. Within 2 years, 14.92% of patients discontinued romiplostim because of adverse events, while 6.47% discontinued because of suspected adverse drug reactions. In contrast, 14.00% of patients discontinued romiplostim because of symptom improvement. Before romiplostim initiation, platelet count was < 2.0 × 104/µL in 60.54% of patients, and the mean platelet count was 2.84 ± 5.76 × 104/µL. Platelet count was 9.19 ± 13.01 × 104/µL after 4 weeks, and remained between 10.34 ± 10.72 and 12.38 ± 12.63 × 104/µL from 8 to 104 weeks of treatment. No specific concerns were revealed regarding the safety and effectiveness of romiplostim in chronic ITP; the findings demonstrated a favorable risk-benefit balance for romiplostim in this population. Trial registration: UMIN000047864 ( www.umin.ac.jp/ctr ).

Exploring the Diagnostic Odyssey of IgA Vasculitis.

IgA vasculitis is a form of small vessel vasculitis characterized by IgA immune complex deposition. Although primarily affecting children, it can also occur in adults, often with more severe manifestations and a higher risk of chronic kidney disease (CKD). The authors present the case of a 77-year-old man with significant cardiovascular risk and atrial fibrillation who was admitted to the emergency department (ED) with pruritic and painful palpable purpuric rash, weight loss, and asthenia persisting for approximately one month prior to presentation. Laboratory findings revealed normocytic normochromic anemia, worsening renal function, elevated inflammatory markers, and leukoerythrocyturia. Initially diagnosed as infectious purpura associated with urinary tract infection, the patient was discharged with a prescription for antibiotics (cefixime). Subsequent worsening of the skin lesions, constitutional symptoms, and gross hematuria prompted a second visit to the ED, and the persistent deterioration of kidney function and inflammatory parameters led to admission for further investigation and consideration of a kidney biopsy. This case report describes the etiological investigation, providing a brief review of the typical characteristics of this disease and highlighting the importance of certain factors in establishing the diagnosis, notably the need and timing of a biopsy of the affected organ for a definitive diagnosis. Additionally, the clinical case underscores the diagnostic challenge, particularly when histological confirmation is elusive.

Drug-free remission of immune thrombocytopenic purpura following resection of perihilar cholangiocarcinoma: a case report.

Immune thrombocytopenic purpura (ITP) is a rare autoimmune disorder. Although secondary ITP, caused by various underlying diseases, including some malignant tumors, has been reported, instances of ITP resolving after successful treatment of the underlying cause are uncommon and noteworthy. Herein, we present a case of a patient with perihilar cholangiocarcinoma (pCCA) and ITP who achieved drug-free remission of ITP following tumor resection. A 76-year-old man presented with pCCA complicated by ITP. Prednisolone treatment successfully managed his thrombocytopenia, allowing for a left hepatopancreatoduodenectomy. ITP relapse did not occur after discontinuation of prednisolone postoperatively. This case suggests that surgical resection of the underlying malignancy may induce remission of secondary ITP associated with pCCA.

Anti-Inflammatory Cytokine Profiles in Thrombotic Thrombocytopenic Purpura-Differences Compared to COVID-19.

Thromboinflammation/immunothrombosis plays a role in several diseases including thrombotic thrombocytopenic purpura (TTP) and COVID-19. Unlike the extensive research that has been conducted on COVID-19 cytokine storms, the baseline and acute phase cytokine profiles of TTP are poorly characterized. Moreover, we compared the cytokine profiles of TTP and COVID-19 to identify the disease-specific/general characteristics of thromboinflammation/immunothrombosis. Plasma concentrations of 33 soluble mediators (SMs: cytokines, chemokines, soluble receptors, and growth factors) were measured by multiplex bead-based LEGENDplex™ immunoassay from 32 COVID-19 patients (32 non-vaccinated patients in three severity groups), 32 TTP patients (remission/acute phase pairs of 16 patients), and 15 control samples. Mainly, the levels of innate immunity-related SMs changed in both diseases. In TTP, ten SMs decreased in both remission and acute phases compared to the control, one decreased, and two increased only in the acute phase compared to remission, indicating mostly anti-inflammatory changes. In COVID-19, ten pro-inflammatory SMs increased, whereas one decreased with increasing severity compared to the control. In severe COVID-19, sixteen SMs exceeded acute TTP levels, with only one higher in TTP. PCA identified CXCL10, IL-1RA, and VEGF as the main discriminators among their cytokine profiles. The innate immune response is altered in both diseases. The cytokine profile of TTP suggests a distinct pathomechanism from COVID-19 and supports referring to TTP as thromboinflammatory rather than immunothrombotic, emphasizing thrombosis over inflammation as the driving force of the acute phase.

The relationship between the severity and complications of Henöch-Schönlein purpura in children and dietary inflammatory index: a retrospective cohort study.

Purpose: To investigate the association between the Dietary Inflammatory Index (DII) and disease severity as well as complications in children diagnosed with Henöch-Schönlein purpura (HSP), shedding light on the potential influence of dietary factors on HSP. Methods: A retrospective cohort study was conducted, enrolling children aged 2-14 years diagnosed with HSP. Participants were divided into low and Pro-inflammatory dietary groups based on their DII scores. Biomarkers, nutrient intake, blood lipid profiles and disease complications were compared between the two groups. Spearman correlation analysis was performed to assess the relationship between DII and complications. Results: A total of 115 patients, including 56 patients with anti-inflammatory dietary and 59 with pro-inflammatory dietary, were included. The pro-inflammatory dietary group demonstrated significantly elevated of C-reactive protein, tumor necrosis factor-α, interleukin-6, erythrocyte sedimentation rate, white blood cell count, eosinophils, IgE, consumption of total calories, protein, carbohydrates, fiber, fat intake, total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, VLDL cholesterol, complications of renal, skin, gastrointestinal, coagulation and respiratory in comparison to the anti-inflammatory dietary group. DII was positively correlated with renal, skin, gastrointestinal, coagulation and respiratory complications. Conclusion: The study highlights the potential influence of dietary inflammatory potential, as quantified by the DII, on disease severity and complications in children with HSP. Understanding the interplay between dietary patterns and inflammatory responses in pediatric vasculitis has implications for the management of HSP, emphasizing the relevance of considering dietary interventions to optimize clinical outcomes and improve the overall well-being of affected children.

Diagnostic utility of direct immunofluorescence test panels for cutaneous vasculitis: A scoping review.

BACKGROUND: Due to the immune-mediated nature of non-infectious cutaneous vasculitis, skin biopsy specimens are often submitted for direct immunofluorescence (DIF) testing when vasculitis is considered clinically. However, evidence regarding the clinical value of DIF has not been rigorously appraised. OBJECTIVE: In this scoping review, we aimed to systematically evaluate the peer-reviewed literature on the utility of DIF in vasculitis to assist with the development of appropriate use criteria by the American Society of Dermatopathology. METHODS: Two electronic databases were searched for articles on DIF and vasculitis (January 1975-October 2023). Relevant case series involving more than or equal to three patients, published in English, and with full-text availability were included. Additional articles were identified manually via reference review. Due to study heterogeneity, findings were analyzed descriptively. RESULTS: Of 255 articles identified, 61 met the inclusion criteria. Cumulatively representing over 1000 DIF specimens, several studies estimated DIF sensitivity to be 75%. While vascular immunoglobulin A (IgA) deposits on DIF were associated with renal disease, other systemic associations were inconsistent. Vascular IgG deposition may be overrepresented in ANCA-associated vasculitis. Granular vascular and epidermal basement membrane zone Ig deposition differentiated hypocomplementemic from normocomplementemic urticarial vasculitis. Few studies have assessed the added value of DIF over routine microscopy alone in vasculitis. CONCLUSIONS: This scoping review discovered that DIF testing for vasculitis has been performed not only for diagnostic confirmation of vasculitis but also for disease subtype classification and prediction of systemic associations. Future studies on test sensitivity of DIF compared to that of histopathology are needed.

Dermatological Manifestations of Disseminated Bacillus Calmette-Guerin Infection in the Intensive Care Unit.

We report a case of disseminated Bacillus Calmette-Guerin (BCG)-itis with zosteriform skin eruption, purpura, and livedo racemosa in a 70-year-old critically ill patient who has a history of in situ bladder carcinoma treated with intravesical BCG instillations for the last three years. He presented with fever, fatigue, and a painful lesion on his back, initially diagnosed as herpes zoster. Despite antiviral treatment, he exhibited persistent fever, an inflammatory syndrome, and mild liver enzyme elevation. Initial imaging revealed findings consistent with pneumonia, for which antibiotics were prescribed with no improvement. A subsequent fluorodeoxyglucose (FDG) PET scan identified hypermetabolic lesions in the liver, prompting a biopsy that showed non-caseating granulomas. Skin biopsies from the zosteriform papular eruption on the back and purpura with livedo racemosa on the right foot revealed non-caseating granulomas. Specific Wade Fite staining performed on skin biopsies indicated evidence of mycobacterial infection. Additionally, cultures and Ziehl-Nielsen staining of blood and bone marrow confirmed Mycobacterium bovis infection, establishing the diagnosis of disseminated BCG-itis. Treatment with rifampicin, ethambutol, and moxifloxacin, and a later switch to isoniazid, along with corticosteroids, resolved the skin lesions and improved the patient's condition. This case underscores the diagnostic challenges and the importance of considering disseminated BCG-itis in patients treated with prior intravesical BCG instillations for in situ bladder carcinoma presenting with persistent fever, multi-organ involvement, and diverse skin manifestations including zosteriform papules, purpura, and livedo racemosa.

Prosthetic Rehabilitation for a Patient With Purpura Fulminans Undergoing Quadruple Amputation: A Case Report.

Purpura fulminans (PF) is a rare and life-threatening syndrome characterized by cutaneous purpura resulting from disseminated intravascular coagulation (DIC) and intravascular thrombosis. PF typically develops as a severe complication of infections and is associated with high mortality rates. Effective treatment involves early recognition, aggressive resuscitation, appropriate antibiotic therapy, and the correction of coagulation abnormalities. Nevertheless, despite effective treatment, patients often ultimately require amputation of the affected limbs. This case report details the rehabilitation process of a patient with PF who underwent quadruple amputation. The patient, a 48-year-old male, underwent quadruple amputation due to PF. After intensive care, he was admitted to a convalescent rehabilitation ward for prosthetic rehabilitation. The rehabilitation process combined physical and occupational therapy to facilitate independent living through the use of upper and lower limb prostheses and assistive devices. The patient presented with ulcerative lesions on the anterior surfaces of both knee joints upon admission. During treatment, he developed osteomyelitis of the right patella, which required intravenous antibiotics and limited rehabilitation to bed-based exercises. Following the administration of intravenous therapy, the prosthetist proceeded with the fabrication of lower limb prostheses. Subsequently, the patient was able to commence standing and gait training, and by the time of discharge, he was able to walk without a cane. Upper limb prostheses enabled independence in activities of daily living (ADLs) such as eating, dressing, and toileting. He was also able to perform cooking-related activities that are part of the instrumental activities of daily living (IADLs). This case highlights the importance and achievable outcomes of rehabilitation for patients with PF who have undergone quadruple amputation. A multidisciplinary approach utilizing both upper and lower limb prostheses, as well as assistive devices, enabled significant functional recovery.

SARS-CoV-2 as a trigger of IgA vasculitis: a clinical case and literature review.

Coronavirus Disease 2019 (COVID-19), caused by SARS-CoV-2, has negatively affected global health. COVID-19 has been associated with a variety of autoimmune and inflammatory disorders, complicating its respiratory manifestations. SARS-CoV-2 triggers inflammatory reactions which may involve multiple organs and systems. The proof for IgA involvement in the immune reactions to coronavirus infection is growing, particularly in the case of IgA immune complex deposition diseases such as IgA vasculitis (IgAV) and IgA nephropathy.This report presents a case of IgAV caused by SARS-CoV-2 in a 53-year-old man. His symptoms included papillomatous, bright red rashes, urticaria throughout the body, aphthous stomatitis, pain in all joints and muscles, weakness, malaise, abdominal pain, face swelling, and arterial hypertension (160/100 mmHg). He received intravenous methylprednisolone (250 mg) and then oral methylprednisolone (16 mg) treatment, which improved his condition. This improvement included the disappearance of abdominal and joint pain and skin rashes.This article also provides an overview of published cases of IgAV after SARS-CoV-2. It may alert rheumatologists and allied specialists of clinical features of IgAV and guide them how to diagnose and treat this disease.

Thrombotic Thrombocytopenia Purpura (TTP) following emergent aortic valve replacement after a complicated TAVR procedure: a case report and review of the literature.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare hematological disorder. The occurrence of TTP subsequent to an emergent aortic valve replacement after a TAVR procedure is exceedingly uncommon with only a few reported cases worldwide. CASE PRESENTATION: We report the case of a 70-year-old female patient diagnosed with aortic insufficiency. Following a transcatheter aortic valve replacement, she underwent emergency aortic valve replacement under cardiopulmonary bypass on the subsequent day due to heart valve displacement. The postoperative diagnosis revealed TTP and symptomatic treatment involving plasma exchange was administered. After demonstrating steady improvement, the patient was eventually discharged. CONCLUSION: Aortic valve replacement after TAVR is a high-risk procedure and increases susceptibility for developing secondary TTP. The diagnosis and treatment of secondary TPP is considerably challenging, and early diagnosis with symptomatic treatment including plasma exchange can increase patient survival.

Proanthocyanidins alleviate Henoch-Schönlein purpura by mitigating inflammation and oxidative stress through regulation of the TLR4/MyD88/NF-κB pathway.

OBJECTIVE: Investigate Proanthocyanidins (PCs) efficacy and mechanisms in treating Henoch-Schönlein purpura (HSP)-like rat models, focusing on inflammatory and oxidative stress (OS) responses. METHODS: An HSP-like rat model was established using ovalbumin (OVA) injection, leading to symptoms mimicking HSP. The study measured inflammatory markers (IL-4, IL-17, TNF-α), OS markers (MDA, SOD, CAT), and assessed the TLR4/MyD88/NF-κB signaling pathway's involvement via histopathological and immunofluorescence analyses. RESULTS: PCs treatment significantly improved HSP-like symptoms, reduced inflammatory cell infiltration, and decreased IgA deposition in renal mesangial areas. Serum analyses revealed that PCs effectively lowered IL-4, IL-17, TNF-α, and MDA levels while increasing SOD and CAT levels (p < 0.05). Crucially, PCs also downregulated TLR4, MyD88, and NF-κB expressions, highlighting the blockage of the TLR4-mediated signaling pathway as a key mechanism. CONCLUSION: PCs show promising therapeutic effects in HSP-like rats by mitigating inflammatory responses and oxidative damage, primarily through inhibiting the TLR4/MyD88/NF-κB pathway. These findings suggest PCs as a potential treatment avenue for HSP, warranting further investigation.

Concurrent Miller Fisher Syndrome and Immune Thrombocytopenic Purpura: A Case Report and Review of the Literature.

Guillain-Barre syndrome (and its subvariants) and immune thrombocytopenic purpura, while both autoimmune disorders provoked by viral infection, rarely coincide. We present the case of a young man who developed both conditions after URI, review prior cases of comorbidity in the literature, and describe their pathophysiology, diagnosis, and management.

Evaluating the Effectiveness of Laparoscopic Removal of an Accessory Spleen After a Failed Splenectomy for Immune Thrombocytopenia.

Immune thrombocytopenic purpura (ITP) is a challenging condition to manage especially when conventional treatment methods, including splenectomy, fail. This report evaluates the effectiveness of laparoscopic removal of accessory spleen for chronic refractory ITP after an initial splenectomy. A 73-year-old African American male with a history of ITP, previously treated with laparoscopic splenectomy nine years ago, presented with severe thrombocytopenia that was found to be refractory to medical therapies. Platelet counts were monitored, and the absence of Howell-Jolly bodies was noted in the peripheral blood smear. Imaging studies over the past eight years indicated the growth of a mass in the left upper abdomen, suggesting a possible accessory spleen. Given the overwhelming evidence of a splenule in refractory thrombocytopenia, laparoscopic exploration and mass removal were conducted. Histologic analysis of the removed mass confirmed a splenule. Despite the complete removal of the mass, postoperative platelet counts remained consistently low and unresponsive to the resumption of medical therapies. This study emphasizes the limitations of accessory splenectomy for refractory ITP and highlights the need for further research to clarify the long-term effectiveness of this surgical procedure in these patients.

A comparative study of anti-ADAMTS-13 antibody dynamics in immune-mediated thrombotic thrombocytopenic purpura.

Background: Thrombotic thrombocytopenic purpura, particularly its immune-mediated variant (iTTP), necessitates accurate diagnostic approaches for effective management. Objectives: To compare a chemiluminescence immunoassay (CLIA) and an enzyme-linked immunosorbent assay (ELISA) for testing ADAMTS-13 activity and detecting anti-ADAMTS-13 autoantibodies (AAbs) in patients with iTTP. Methods: This study involved 31 paired samples from 12 iTTP patients. ADAMTS-13 activity was measured using the HemosIL AcuStar (Instrumentation Laboratory, CLIA) and Technozym (Technoclone) activity assay (ELISA). The presence of AAbs was assessed using Technozym ADAMTS-13-INH assay (ELISA) and HemosIL AcuStar activity (CLIA) within a Bethesda assay following mixing with normal pool plasma. von Willebrand factor (VWF) multimers were analyzed using the HYDRASYS-2 SCAN system and the HYDRAGEL 5- or 11-VW Multimer kits (Sebia). VWF activity levels were measured with the HemosIL AcuStar VWF:GPIbR on the ACL AcuStar Analyzer (IL). Results: For ADAMTS-13 activity, a strong linear relationship and no bias between CLIA and ELISA were confirmed (slope = 1.01 [0.91, 1.11], intercept = 0.00 [-0.47, 0]). However, significant discrepancies were found in AAb detection during remission phases with ADAMTS-13 activity between 10% and 50%, with CLIA and ELISA showing significant divergence (P < .001, Cohen's g = 0.34). Consistently, VWF multimers and activity levels exhibited significantly different values between remission samples with ADAMTS-13 activity below 50% and above 50%. In longitudinal analysis of patients with multiple iTTP relapses, positivity to CLIA appears to precede ELISA in predicting exacerbations. Conclusion: While CLIA and ELISA might be interchangeable for assessing ADAMTS-13 activity, they are not equivalent for detecting AAbs, particularly in patients in clinical remission with ADAMTS-13 activity between 10% and 50%.