Thrombotic thrombocytopenic purpura with acute anuric renal failure

Thrombotic Thrombocytopenic Purpura

Thrombotic thrombocytopenic purpura (TTP) is classically highlighted by a pentad of features: fever, hemolytic anemia, thrombocytopenia purpura, transient or permanent central nervous system signs, and renal disease. The antemortem diagnosis is reliant upon the multisystem clinical signs and symptoms in conjunction with severe hemolytic anemia and thrombocytopenia. Relapse is common within the first six months after initial presentation. Laboratory findings have been generally nonspecific per se, and antemortem tissue biopsy findings are frequently unrewarding. Recently, however, unusually large multimers of the Factor VIII:Ag molecule (von Willebrand protein) have been identified in the plasma of patients with TTP who have recovered from an acute attack. This observation is very important because it may lead to essential information on the nature of the inciting event in this devastating illness. The differential diagnosis includes several multisystem disease processes such as the hemolytic uremic syndrome, toxemia of pregnancy, systemic lupus erythematosus, subacute bacterial endocarditis, nonbacterial thrombotic endocarditis, immune thrombocytopenic purpura, and the postpartum renal failure syndrome. The hemolytic uremic syndrome, toxemia of pregnancy, and TTP may resemble each other, exhibit many overlapping features, and are probably related. The cause of TTP remains unknown; the overwhelming majority of cases occur in otherwise healthy people without any recognizable underlying illness. Since 1965 45 to 70% of patients survive, a significant improvement in contrast to the early 1900s when the mortality rate was greater than 90%. The most dramatic advance has been observed in therapeutics, namely the utilization of some mode of plasma therapy (either infusion alone or plasmapheresis followed by plasma infusion). Corticosteroids remain very important in the management of patients with TTP. Vincristine may be very helpful, but additional studies are needed. The efficacy of vinca alkaloids, chronic immunosuppressive therapy, and sple. nectomy remains undefined. At present there is very little, if any, evidence that antiplatelet agents, aspirin, and prostacyclin are beneficial to patients with TTP. Prompt diagnosis and vigorous aggressive therapy is critical for successful management of TTP patients.

Thrombotic thrombocytopenic purpura associated with severe acute pancreatitis in a context of decreased ADAMTS13 activity: a case report

Thrombotic thrombocytopenic purpura (TTP) is a severe multisystemic microvascular disease defined by the association of hemolytic anemia, thrombocytopenia, acute renal failure, fever, and neurological disorders. The pathophysiology has recently been elucidated by the discovery of a von Willebrand factor-cleaving protease (ADAMTS13) deficiency involved in platelet aggregation and ischemia. The association between TTP and acute pancreatitis (AP) has rarely been reported, described either as a cause or a consequence. The role of ADAMTS13 during AP is still unknown. We describe the case of a 41-year-old woman who developed a TTP, with decreased ADAMTS13 activity, associated with severe AP. Published cases of thrombotic microangiopathy associated with AP are reviewed. The pathophysiology, management, prognostic factors, and rationale for treatment are discussed. AP should be sought in patients with TTP presenting with abdominal pain. On the other hand, TTP should be considered in patients with AP and thrombocytopenia.

The fibrinolytic system attenuates vascular tone: effects of tissue plasminogen activator (tPA) and aminocaproic acid on renal microcirculation

1. The renal medulla is a major source of plasminogen activators (PA), recently shown to induce vasodilation in vitro. Treatment with PA inhibitors has been associated with renal dysfunction, suggesting compromised renal microvasculature. We investigated the impact of the PA inhibitor epsilon amino-caproic acid (EACA) upon vascular tone in vitro, and studied the effect of both tPA and EACA upon intrarenal hemodynamics in vivo. 2. In vitro experiments were carried out in isolated aortic rings and with cultured vascular smooth muscle cells. Studies of renal microcirculation and morphology were conducted in anesthetized Sprague-Dawley rats. 3. In isolated aortic rings, EACA (but not the other inhibitors of the fibrinolytic system PAI-1 or alpha-2 antiplasmin) reduced the half-maximal effective concentration of phenylephrine (PE) required to induce contraction (from 32 nm in control solution to 2 and 0.1 nm at EACA concentrations of 1 and 10 microm, respectively). Using reteplase (retavase) in the same model, we also provide evidence that the vasoactivity of tPA is in part kringle-dependent. In cultured vascular smooth muscle cells, Ca(2+) internalization following PE was enhanced by EACA, and retarded by tPA. 4. In anesthetized rats, EACA (150 mg x kg(-1)) did not affect systemic blood pressure, total renal or cortical blood flow. However, the outer medullary blood flow declined 12+/-2% below the baseline (P<0.03). By contrast, tPA (2 mg x kg(-1)), transiently increased outer medullary blood flow by 8+/-5% (P<0.02). Fibrin microthrombi were not found within the renal microvasculature in EACA-treated animals. 5. In conclusion, both fibrinolytic and antifibrinolytic agents modulate medullary renal blood flow with reciprocal effects of vasodilation (PA) and vasoconstriction (EACA). In vitro studies suggest that these hemodynamic responses are related to direct modulation of the vascular tone.

The gingival biopsy in the diagnosis of thrombotic thrombocytopenic purpura

Gingival biopsy specimens from five patients with a clinical diagnosis of thrombotic thrombocytopenic purpura (TTP) were reviewed. All biopsy specimens demonstrated the characteristic histologic lesion associated with TTP. Review of the literature showed an average diagnostic yield of 37% (30/81) for this procedure. The increase in diagnostic correlation in this study may be explained in part by the marked degree of disease expression in the patients who underwent gingival biopsy. Three of the five patients who underwent gingival biopsies ultimately died of their disease. In addition, a persistent search through multiple serial sections for the characteristic lesion, beyond the usual three levels, was performed. Despite the disparity in diagnostic yield, we consider the gingival biopsy to be a safe diagnostic correlate of TTP because of easy access, rich vascularity, and low surgical morbidity. Furthermore, we recommend biopsy, as Goodman and colleagues have, only in areas of the gingiva that appear clinically normal and free of inflammation in order to reduce misinterpretation as a consequence of false-positive intraluminal fibrin thrombi that may occur with inflammation.

Recurrent thrombotic microangiopathy in a renal allograft. Case report and review of the literature

Thrombotic microangiopathy in a renal allograft may either reflect a recurrence of the patient's original disease, i.e., thrombotic thrombocytopenic purpura, hemolytic-uremic syndrome, or more commonly may be a manifestation of allograft rejection. This report describes a patient in whom irreversible renal failure developed during thrombotic thrombocytopenic purpura. Two years later while her condition was in clinical remission, she received a 2 DR-matched cadaveric allograft. Nineteen days following transplantation, thrombotic microangiopathy developed in the graft with eventual loss of allograft function despite vigorous plasmapheresis therapy. Multiple factors in addition to possible recurrent disease that may have contributed to this event were identified. The literature on thrombotic microangiopathy and renal transplantation is reviewed.

Adult hemolytic-uremic syndrome: successful treatment with plasmapheresis

Two adult patients with the hemolytic-uremic syndrome were treated successfully with intense plasma exchange. One patient had recurrent episodes and, with each relapse, both their thrombocytopenia and acute renal failure were reversed with plasma exchange therapy alone. These cases demonstrate the useful role of plasma exchange in the therapy of severe idiopathic hemolytic-uremic syndrome in adults.

Thrombotic thrombocytopaenic purpura and anuria: response to plasma exchange

This report discusses the treatment and recovery of a 29-year-old woman with thrombotic thrombocytopaenic purpura complicated by servere renal failure. The case is reported because of the rarity of recovery from anuric renal failure in this disease and the probable contribution of plasma exchange to this recovery.

Transplantation in the hemolytic-uremic syndrome

A case history of a fifty-seven-year-old white woman with hemolytic-uremic syndrome who was successfully transplanted with a cadaver homograft is reported. A review of the pertinent literature regarding the pathophysiology of the syndrome and the experience to date with transplantation is presented.

Thrombotic thrombocytopenic purpura in four siblings

A family is described in which four members of a sibship of seven suffered from a hematologic and systemic disorder whcih has been fatal in three and has been proved at autopsy to have been fatal in three and has been proved at autopsy to have been thrombotic purpura. The fourth member has probably suffered the same disorder. The clinical laboratory and genetic features of the family are discussed at length. No cause of the disorder has been determined.

Moschcowitz syndrome with involvement of the central nervous system. Light optical studies on the genesis of hemolytic anemia and vascular changes

The origin of hemolytic anemia, the histogenesis of vascular changes and the origin of prethrombotic lesion are discussed in a typical case of thrombotic thrombocytopenic purpura (TTP) with early neurological symptoms. The disease arose after exposure to a chloronaphtalene containing substance. In addition to the typical vascular changes of different age, early non-endothelialised and non obstructing aggregates of fibrin and thrombocytes are observed. Clusters of drop-like deformed erythrocytes and elongated leucocytes are attached to their surface. These changes do not appear to have been reported previously in TTP. The fresh thrombi are regarded as being hematologically active. Support for their supposed causal relationship to hemolytic anemia is given by experimental data by Brain and Bull.

Ocular findings in thrombotic thrombocytopenic purpura (Moschcowitz's disease)

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Thrombotic microangiopathy in rheumatoid arthritis

The syndrome of thrombotic microangiopathy is described in an elderly woman with active rheumatoid arthritis and thyroiditis. Phenylbutazone and imipramine were used in treatment immediately before thrombocytopenia was recognised and the possible role of these drugs in precipitating microvascular thrombi in rheumatoid arthritis is discussed.