COVID-19 associated thrombotic thrombocytopenic purpura (TTP) ; A case series and mini-review.

INTRODUCTION: Thrombotic microangiopathies are a group of disorders that are mainly related to endothelial dysfunction. This category of endothelial dysfunction results of several imbalances between platelets, endothelium and immune system, also cytokine production. AIM OF THIS STUDY: To report cases with thrombotic thrombocytopenic purpura (TTP) and COVID-19 and review COVID-19 endothelial dysfunction literature. METHODS: Primary laboratory data, peripheral blood smear, ADAMTS13 antigen activity level, and antibody ordered for each of these four patients. Treatments for COVID-19 administered for all patients. Traditional treatments for TTP also were administered. RESULTS: There were numerous schistocytes (more than 5%) in peripheral blood smears for each patient. ADAMTS13 antigen activity level was below 10%, and ADAMTS13 antibody was elevated for each patient. COVID-19 PCR was positive for all patients, and CT-Scans were indicative of the involvement of COVID-19. CONCLUSION: In this case series, we reported four COVID-19 patients who presented with signs and symptoms of anemia and thrombocytopenia, resulting in thrombotic thrombocytopenic purpura.

Cytomegalovirus induced refractory TTP in an immunocompetent individual: a case report.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare, potentially fatal disease with multisystem involvement. Cytomegalovirus (CMV) infection as a cause of refractory TTP, has been reported only in immunocompromised individuals. We report a case of CMV-induced refractory TTP in an immunocompetent individual. CASE PRESENTATION: A 35-year-old, previously healthy Sri Lankan man, presented with fever for 3 days with gum bleeding and progressive drowsiness. His Glasgow coma scale score was 10/15. He did not have papilloedema or neck stiffness. Laboratory evaluation showed a severe thrombocytopenia with microangiopathic haemolytic anaemia. There was marginal renal impairment and normal coagulation profile. Non-contrast CT scan of brain was normal. A diagnosis of thrombotic thrombocytopenic purpura was made. Despite daily plasma exchanges and high-dose steroids, he failed to achieve the expected therapeutic response, thus demonstrating refractory TTP. On exploring for possible causes of refractoriness to treatment, a clinically significant PCR titre of CMV was detected. Treatment of CMV infection lead to complete recovery of TTP. His disease course was further complicated with spontaneous spinal haemorrhage leading to neurological sequelae. DISCUSSION AND CONCLUSIONS: This is the first report of CMV induced refractory TTP in an immunocompetent adult. It is also the first report of clinically significant spontaneous spinal haematoma in TTP. These two rare occurrences should be considered when patients with refractory TTP do not improve as expected.

HIV-associated thrombotic thrombocytopaenic purpura: A retrospective cohort study during the anti-retroviral therapy era.

BACKGROUND: HIV-associated thrombotic thrombocytopaenic purpura (TTP) is thought to represent the majority of current TTP diagnoses in South Africa (SA). AIM: The primary aim was to describe the clinical features and compare the time to remission of TTP in those patients with and without HIV. DESIGN: A retrospective cohort study conducted at Tygerberg Hospital in Cape Town, SA for the period January 1, 2010 to January 31, 2015. METHODS: All adult patients requiring ≥5 units of plasma products for ≥1 day during hospitalization were screened for a diagnosis of TTP. Those with a reported clinical diagnosis and/or laboratory evidence of TTP were included in the final analysis. RESULTS: A total of 52 cases were identified of which 78.8% were HIV-infected. Time to remission was 10 days in the HIV group vs 19 days in the HIV negative group, P = 0.07. Most of the patients were Black females. Fever was more common in those with HIV. Neurological features were common in both groups. The majority in the HIV group was managed exclusively with plasma infusion alone (90.2% vs 45.5%, P < 0.01). There were no differences in the time to remission regardless of treatments received. Anti-retroviral therapy initiation during hospitalization was a predictor for remission. Overall mortality rate was 44.2%. CONCLUSION: There was no difference in the time to remission in patients with HIV-associated TTP as compared with HIV negative TTP. The high mortality was probably the result of less intensive plasma infusion and therapeutic plasma exchange regimens.

Thrombotic thrombocytopenic purpura: A 5-year tertiary care centre experience.

INTRODUCTION: Thrombotic thrombocytopenic purpura (TTP) is associated with high mortality if not managed timeously with therapeutic plasma exchange (TPE). TTP secondary to human immunodeficiency virus (HIV) infection is unique to sub-Saharan Africa. The management and outcome of TTP in the era of improved access to therapy has not been described. METHODS: The present study describes the clinical presentation, treatment, therapeutic endpoints, and outcome of TTP patients at the Charlotte Maxeke Johannesburg Academic Hospital, South Africa. The inpatient and outpatient records of 41 consecutive adults with TTP were reviewed between 2012 and 2016. Patients were classified according to aetiology and treatment response. RESULTS: TTP was the initial presenting feature of HIV infection in 78.0%, and 12.5% were noncompliant with antiretroviral therapy (ART). Most study patients were of black ethnicity (95%) and female gender (78.1%). Treatment included initial TPE (87.8%), plasma infusion (78.1%), antiretroviral therapy (78.3%), corticosteroids (61.0%) intensive care admission (41.5%), renal dialysis (12.2%), and other immunosuppressive agents (4.9%). The median (range) number of TPEs was 10.0 (7.0-15.0). A high rate of refractory disease (63.4%) was reported. Haemoglobin, platelet count, lactate dehydrogenase, red cell distribution width, and creatinine were reliable therapeutic end-points (P < .05). The relapse rate was 9.8% and the mortality rate was 29.3%. CONCLUSION: The high mortality rate emphasises the importance of early diagnosis, referral, and appropriate management of TTP. Anti-retroviral therapy and adherence monitoring are essential to TTP management associated with HIV. Future studies to identify patients at risk for refractory disease are indicated.

Thrombotic thrombocytopenic purpura associated with dengue and chikungunya virus coinfection: case report during an epidemic period.

The present report shows the occurrence of thrombotic thrombocytopenic purpura (TTP) associated with acute dengue and chikungunya virus coinfection, manifesting as a severe disease with high mortality potential. The patient was a 28 year-old man with clinical and epidemiological diagnosis of arboviruses infections who developed thrombocytopenia and anemia, after which oral corticosteroid therapy was started. On the third day of hospitalization, he showed neurological alterations that simulated a cerebral vascular accident, but the imaging examination did not identify ischemic or hemorrhagic alterations. At that moment, the TTP hypothesis was raised so that plasmapheresis and corticosteroid pulse therapy were started, have been essential for the favorable evolution of the case.

Thrombotic microangiopathy in the setting of human immunodeficiency virus infection: High incidence of severe thrombocytopenia.

BACKGROUND: Human immunodeficiency virus (HIV) infection increases the risk of thrombotic microangiopathy (TMA), but TMA in the setting of HIV infection is not well characterized. The experience with TMA in the setting of HIV infection at the University of Maryland Medical Center was reviewed. STUDY DESIGN AND METHODS: Patients undergoing therapeutic plasma exchange (TPE) for TMA from January 1, 2000 through December 31, 2012 were reviewed. Those with known HIV-positive and -negative status were compared. RESULTS: Among 102 patients with known HIV status, 28 (27%) were HIV-positive, including 3 with previously undiagnosed HIV. HIV-positive patients had a median viral load of 89 500 copies/mL (range, 0->750 000 copies/mL) and a median CD4 count of 58 cells/µL (range, 2-410 cells/µL). Compared to HIV-negative patients, HIV-positive patients more frequently presented with concurrent infections (60.7% vs. 23.7%; P = .0007), had a trend toward lower median platelet counts (3000/µL vs. 15 000/µL; P = .07) and more frequently had platelet counts less than 10 000/mcL (P = .02). Nevertheless, number of TPE procedures required for remission, remission rate, mortality, and relapse incidence were similar in HIV-positive and HIV-negative patients. CONCLUSIONS: The incidence described herein of HIV infection among TMA patients is the highest reported outside of South Africa. More severe thrombocytopenia in HIV-positive patients may reflect TMA in the setting of preexisting HIV-associated thrombocytopenia. HIV should be considered in patients with TMA, and TMA should be considered in HIV-positive patients with severe thrombocytopenia.

Thrombotic Thrombocytopenic Purpura in a Child Treated for Acute Lymphoblastic Leukemia: Case Report and Review of Literature.

Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy caused by deficiency of von Willebrand factor-cleaving protease ADAMTS13. Large von Willebrand multimer formation and intravascular platelet aggregation affecting the arterioles and capillaries can result in death unless early treatment is administered. We report on the case of a child with TTP associated with a human herpes virus type-6 infection occurring during chemotherapy for acute lymphoblastic leukemia who was effectively treated by fresh frozen plasma infusions and antiviral therapy. Although rarely observed in children affected by acute lymphoblastic leukemia, TTP is a potentially fatal illness that should be considered in the differential diagnosis of thrombocytopenia with hemolytic anemia.

Chikungunya Fever Presenting as Life Threatening Thrombotic Thrombocytopenic Purpura.

It is well known for Chikungunya fever to present as myriad of skin rash along with usual joint pain and fever, but probably this is the first case report of Chikungunya fever presenting as severe life threatening thrombotic microangiopathy, thrombotic thrombocytopenic purpura leading to multiple areas of skin necrosis, peripheral digital gangrene, haemolytic anemia, renal failure and severe thrombocytopenia with bleeding. This complication was most likely due to inhibitor autoantibody formation against ADAMTS13 triggered by chikungunya virus leading to thrombotic thrombocytopenic purpura. Patient was treated with plasmapheresis and other supportive careto which she responded. Her symptoms subsided, and she is symptom free and leading normal life in her follow up visits.

Human immunodeficiency virus associated thrombotic thrombocytopenic purpura, a clinical conundrum.

HIV complicates the diagnostic and therapeutic approaches to idiopathic thrombotic thrombocytopenic purpura (TTP), prompting debate in the literature regarding the benefit of plasma exchange versus simple plasma infusion. Herein we present a case of HIV-TTP, initially treated conservatively with plasma infusion but because of progressive neurologic decline, required urgent plasma exchange for resolution of hematologic derangements and neurologic sequelae. Based on the available literature, there appears to be a spectrum of HIV-associated TTP disorders. Patients with advanced HIV disease and opportunistic infections who present with thrombotic microangiopathy tend to respond to simple plasma infusion, while patients with less progressive HIV disease tend to behave like those with idiopathic TTP, requiring plasma exchange rather than simple plasma infusion. This article illustrates that in patients with HIV-TTP who do not respond to plasma infusion, early escalation to plasma exchange may help avoid life-threatening complications such as seizures and even death.

A novel Wiskott-Aldrich syndrome protein mutation in an infant with thrombotic thrombocytopenic purpura.

Thrombotic thrombocytopenic purpura (TTP) has not yet been reported to be associated with mutations in the Wiskott-Aldrich syndrome (WAS) gene. WAS is an X-linked recessive disorder characterized by thrombocytopenia, small platelet size, eczema, recurrent infections, and increased risk of autoimmune disorders and malignancies. A broad spectrum of mutations in the WAS protein (WASP) gene have been identified as causing the disease. In this study, we report on a 2-month-old Japanese boy who presented with cytomegalovirus (CMV) infection and TTP. The activity of von Willebrand factor cleaving metalloproteinase, ADAMTS13 was low and the antibody against ADAMTS13 was positive (3.6 Bethesda U/mL). Although TTP was improved by plasma exchange and steroid pulse therapy, thrombocytopenia persisted and regular transfusions of irradiated platelets were needed. Tiny platelets were found on a peripheral blood smear. CMV genome was positive in peripheral blood by polymerase chain reaction and the CMV viremia continued to persist despite intravenous gancyclovir therapy. Through direct sequencing of genomic DNA of the WASP gene in the patient, we identified a novel mutation of WASP gene: the seventh nucleotide in exon 11 (G) had been deleted (1345delG). This mutation causes a frameshift and a stop codon at amino acid 470. Western blotting demonstrated a truncated WAS protein. To our knowledge, this is the first report describing TTP in WAS patients with novel mutation in the WASP gene.

Thrombotic thrombocytopenic purpura triggered by influenza A virus subtype H1N1 infection.

We report a case of acquired thrombotic thrombocytopenic purpura (TTP) triggered by influenza A virus subtype H1N1 infection. In December 2010, a 27-year-old man was diagnosed with pneumonia from influenza A virus infection at a local clinic. Two days later, he was admitted to our hospital because of a worsening condition and unexplained thrombocytopenia. The influenza A virus subtype H1N1 real-time polymerase chain reaction test was positive. The patient had typical clinical signs of TTP, thus he was diagnosed with TTP. He received treatment with oseltamivir and high dose methylprednisolone. Plasma exchange therapy was started daily at a 1.5 dose volume of his whole blood. After the 17th plasma exchange therapy, the symptoms and abnormal laboratory results had recovered to normal. Finally, 47 days after admission, the patient had recovered completely and was discharged. This case suggests that the influenza A virus subtype H1N1 infection may have triggered acquired TTP.

The importance of CD4 count, viral load and highly active antiretroviral therapy in HIV-associated thrombotic thrombocytopenic purpura (TTP).

A case is reported of HIV-associated thrombotic thrombocytopenic purpura with normal CD4 count but high HIV viral load, developing neurological and cardiac complications up to 36 days after initiation of plasma exchange, but remitting within 18 days of the start of highly active antiretroviral therapy and steroids. In addition to plasma exchange, prompt initiation of highly active antiretroviral therapy in patients with HIV-associated thrombotic thrombocytopenic purpura may be justified despite a normal CD4 count.

Viral-associated thrombotic microangiopathies.

Thrombotic microangiopathies encompass a group of disorders characterized by microangiopathic hemolytic anemia, thrombocytopenia associated with hyaline thrombi (comprised primarily of platelet aggregates in the microcirculation), and varying degrees of end-organ failure. Many primary (genetic) and secondary etiological predisposing factors have been described-namely pregnancy, autoimmune disorders, cancer, drugs and antineoplastic therapy, bone marrow transplantation/solid organ transplantation, and infections. In the setting of infectious diseases, the association with Shiga or Shiga-like exotoxin of Escherichia coli 0157:h7 or Shigella dysenteriae type 1-induced typical hemolytic uremic syndrome is well known. Recently however, an increasing body of evidence suggests that viruses may also play an important role as trigger factors in the pathogenesis of thrombotic microangiopathies. This is a comprehensive review focusing on the current understanding of viral associated/induced endothelial stimulation and damage that ultimately leads to the development of this life-threatening multisystemic disorder.

Human immunodeficiency virus associated thrombotic thrombocytopenic purpura--favourable outcome with plasma exchange and prompt initiation of highly active antiretroviral therapy.

Thrombotic thrombocytopenic purpura (TTP) is an acute prothrombotic disorder. Human immunodeficiency virus (HIV) is an identified precipitant. This study reviewed 30 episodes of HIV-associated TTP in 24 patients from the South-East England Apheresis units, over the last 10 years. All patients were heterosexual Black Africans. First presentation of TTP revealed a new diagnosis of HIV in eight patients. TTP relapse occurred on six occasions (in four patients) as a result of non-adherence to highly active antiretroviral therapy (HAART). Prompt initiation/re-initiation of HAART in parallel with plasma exchange (PEX)±steroid led to prompt remission. Adjunct immunomodulatory agents (e.g. Rituximab) were required in 10% of cases. Once-daily HAART regimens are recommended, being compatible with PEX requirement, maximizing drug exposure between PEX. High viral loads (>500,000 copies/ml) require more PEX to remission. ADAMTS13 activity was reduced (<5%) as detected by collagen-binding assay and anti-ADAMTS13 immunoglobulin G antibodies were raised in 80%. Continued HAART-adherence ensured a durable TTP remission with associated viral control resulting in no evidence of relapse. PEX and HAART are associated with replenishment of ADAMTS13 and viral suppression. More PEX is required in cases with higher viral loads. Continued HAART maintains remission. In a small proportion of cases, further immunomodulatory therapy may be required.

Thrombotic thrombocytopenic purpura in patients with retroviral infection is highly responsive to plasma infusion therapy.

We prospectively studied presentation biological differences and the response to therapy in patients with thrombotic thrombocytopenic purpura (TTP) associated with, or unrelated to human immunodeficiency virus (HIV) infection. TTP patients underwent standard evaluations and were treated with prednisone 1 mg/kg in addition to infusions of fresh frozen plasma (FFP; 30 ml/kg/d) until normalization of the platelet count. Unresponsive patients were referred for plasma exchange. Compared with HIV- TTP patients (n=23), in HIV+ subjects (n=21) microangiopathy was dominant among Black females, who had lower presentation Hb (median 5.8 g/dl; P=0.03), platelet count (13 x 10(9)/l; P=0.05) and a CD4 count of 0.096 x 10(9)/l. HIV+ individuals responded to FFP faster than HIV- patients and none of them required apheresis. Ten HIV- TTP patients required apheresis (P=0.03) and four died. Responses in the HIV+ and HIV- groups occurred after treatment with a median of 33 and 55 units (one unit=320 ml) of FFP (P=0.004) respectively. Response to this protocol was seen in 84% (95% response in HIV+ patients). Regression analysis showed that survival was associated with younger age (P=0.001), rapid platelet (P=0.001) and Hb (P=0.0009) recovery, and fewer FFP units to normal lactate dehydrogenase levels (P=0.006). We conclude that in HIV+ individuals, microangiopathy is highly responsive to plasma infusions. This observation is important particularly when apheresis is not available.

Thrombotic microangiopathy associated with unusual viral sequences in HIV-1-positive patients.

BACKGROUND: Thrombotic microangiopathy (TMA) is a rare disorder caused by endothelial cell damage. TMA has been associated with the human immunodeficiency virus 1 (HIV-1) infection, yet only a minority of all HIV-1 patients develops TMA. Since HIV-1 has been shown to interact with endothelial cells, we investigated whether certain mutations in the HIV-1 envelope protein are associated with the development of TMA in HIV-1-infected patients. METHODS: Plasma was obtained from nine HIV-1-positive patients with TMA. Viral loads were determined from the samples and compared with the clinical data. Viral envelope protein sequences from the regions known to be responsible for viral tropism were isolated, sequenced and compared with known HIV-1 isolates. The isolates were expressed as synthetic fusion proteins; binding of these fusion proteins to CD4+ cells as well as to endothelial cell lines was investigated. RESULTS: The viral loads in patients with HIV/TMA were highly variable with no correlation to the clinical status. Most patients carried macrophage-tropic viral envelope protein sequences and an unusual insertion was found in the V2 variable region. The isolates showed increased CD4 binding, but a direct binding to endothelial cells was not observed. CONCLUSIONS: Although TMA is generally diagnosed in patients with advanced HIV-1 infection, viral loads per se were not predictive of TMA in this study. While a direct interaction with endothelial cells was not detectable, specific viral envelope mutations were found in a region known to influence viral tropism. Hence, viral-specific factors might contribute to the pathogenesis of HIV-associated TMA.