CMV-related thrombocytopenia treated with foscarnet: A case series and review of the literature

Cytomegalovirus-Associated Nephrotic Syndrome in a Patient with Myasthenia Gravis Treated with Azathioprine: A Case Report

BACKGROUND Patients taking azathioprine (AZA) are very susceptible to development of cytomegalovirus (CMV) infection. The symptoms of CMV infection are varied. In some rare cases, CMV infection can even result in nephrotic syndrome. CASE REPORT Here, we present a rare case of nephrotic syndrome associated with CMV infection, induced by azathioprine intake. The patient, diagnosed with myasthenia gravis, was initially treated with azathioprine for 2 years. Then, the patient was admitted to the hospital due to nephrotic syndrome and acute kidney injury. Minimal change disease with acute tubular necrosis were diagnosed through biopsy. After an initial good response to hemodialysis and steroids, the patient developed severe pneumonia and oral ulcers. Further anti-CMV IHC staining of kidney tissues showed positive cells in tubules, indicating nephrotic syndrome secondary to CMV infection. CONCLUSIONS This case reminded us that CMV may be an under-recognized cause of nephrotic syndrome. Patients treated with azathioprine are very susceptible to developing CMV infection. During the diagnosis of nephrotic syndrome, we should always take CMV infection into consideration, especially in patients with on azathioprine.

HCMV modulates c-Mpl/IEX-1 pathway-mediated megakaryo/thrombopoiesis via PDGFRα and αvβ3 receptors after allo-HSCT

Thrombocytopenia is a common complication of human cytomegalovirus (HCMV) infection in immunocompromised hosts, which contributes to poor prognosis even in patients receiving antiviral treatment. Here, we investigated the megakaryo/thrombopoiesis process, including the involvement of the c-Mpl/IEX-1 pathway, after HCMV infection, identified receptors mediating the interaction between megakaryocytes (MKs) and HCMV, and explored novel therapeutic targets. Our data shows that HCMV directly infects megakaryocytes in patients with HCMV DNAemia and influences megakaryopoiesis via the c-Mpl/IEX-1 pathway throughout megakaryocyte maturation, apoptosis, and platelet generation in vivo and in vitro. After treatment with inhibitors of PDGFRα and αvβ3, the HCMV infection rate in MKs was significantly reduced, suggesting that IMC-3G3 and anti-αvβ3 are potential therapeutic alternatives for viral infection. In summary, our study proposes a possible mechanism and potential treatments for thrombocytopenia caused by HCMV infection and other viral diseases associated with abnormal hemostasis.

Severe immune thrombocytopaenia in a patient taking benznidazole for chronic Chagas disease

Chagas disease is a parasitic disease that mostly affects Latin American countries, but it has currently become a worldwide epidemic due to migration. Both drugs marketed for its treatment (benznidazole and nifurtimox) are associated with a high rate of adverse reactions. Benznidazole is preferred initially because of its more favourable toxicity profile and perceived greater efficacy. Hypersensitivity dermatological reactions, gastrointestinal and neurological disturbances represent the most common drug-related adverse events. General symptoms such as fever, arthralgia, myalgia or bone marrow depression (leucopaenia) are seen less frequently. We describe the case of a 33-year-old woman with chronic Chagas disease who presented with acute gingival bleeding and severe thrombocytopaenia, probably related to benznidazole treatment. Temporal association with drug initiation and recovery after treatment withdrawal were demonstrated. Clinicians should be aware of the possible association between immune thrombocytopaenia and benznidazole, even though the pathogenesis remains unclear at present.

Cytomegalovirus-associated thrombocytopenia treated with thrombopoietin receptor agonist

Symptomatic cytomegalovirus (CMV) in immunocompetent individuals is an uncommon, yet recognised, phenomenon. This report discusses a case of CMV-associated thrombocytopenia refractory to immunomodulation and antivirals. Ultimately, a clinicopathological response was attained with eltrombopag. This is the first report of the efficacy of thrombopoietin receptor agonists in this context. This experience provides insight into possible pathogenic mechanisms of CMV-associated thrombocytopenia and presents a therapeutic option.

Platelets, acting in part via P-selectin, mediate cytomegalovirus-induced microvascular dysfunction

Cytomegalovirus (CMV) infects a majority of the population worldwide. It has been implicated in cardiovascular disease, induces microvascular dysfunction, and synergizes with hypercholesterolemia to promote leukocyte and platelet recruitment in venules. Although platelets and platelet-associated P-selectin contribute to cardiovascular disease inflammation, their role in CMV-induced vascular responses is unknown. We assessed the role of platelets in CMV-induced microvascular dysfunction by depleting platelets and developing bone marrow chimeric mice deficient in platelet P-selectin. Wild-type and chimeric mice received mock or murine (m)CMV intraperitoneally. Five weeks later, some mice were switched to a high-cholesterol diet (HC) to investigate the synergism between mCMV and HC. Arteriolar vasodilation and recruitment of leukocytes and donor platelets in venules were measured at 11wk. mCMV with or without HC caused significant endothelial dysfunction in arterioles. Platelet depletion restored normal vasodilation in mCMV-HC but not mCMV-ND mice, whereas protection was seen in both groups for platelet P-selectin chimeras. Only mCMV + HC elevated leukocyte and platelet recruitment in venules. Leukocyte adhesion was reduced to mock levels by acute platelet depletion but was only partially decreased in platelet P-selectin chimeras. Platelets from mCMV-HC mice and, to a lesser extent, mCMV-ND but not mock-HC mice showed significant adhesion in mCMV-HC recipients. Our findings implicate a role for platelets, acting through P-selectin, in CMV-induced arteriolar dysfunction and suggest that the addition of HC leads to a platelet-dependent, inflammatory infiltrate that is only partly platelet P-selectin dependent. CMV appeared to have a stronger activating influence than HC on platelets and may represent an additional therapeutic target in vulnerable patients.

Congenital cytomegalovirus infection and Wiskott-Aldrich syndrome successfully treated with unrelated cord blood transplantation

We report a successful umbilical cord blood transplantation (UCBT) in an 8-month male with Wiskott-Aldrich syndrome (WAS) and congenital cytomegalovirus (CMV) infection. The child presented at 3 months of age with symptomatic thrombocytopenia and CMV infection. Despite appropriate antiviral treatment no rise in the platelet count was observed. Genetic analysis confirmed the diagnosis of WAS. The clinical course was complicated by severe CMV retinitis with bilateral retinal hemorrhages and renal vasculitis. He underwent unrelated UCBT resulting in a rapid resolution of autoimmunity and thrombocytopenia.