Pulmonary veno-occlusive disease accompanied by microangiopathic hemolytic anemia 1 year after a second bone marrow transplantation for acute lymphoblastic leukemia

Pulmonary Histopathologic Findings in Pediatric Patients After Hematopoietic Stem Cell Transplantation: An Autopsy Study

BACKGROUND

Pathologic characterization of pulmonary complications following hematopoietic stem cell transplantation (HSCT) is limited. We describe lung findings in pediatric patients who died following HSCT and attempt to identify potential clinical associations.

METHODS

Pathology databases at Texas Children's Hospital and the Children's Hospital of Philadelphia were queried (2013-2018 CHOP and 2017-2018 TCH). Electronic medical records and slides were reviewed.

RESULTS

Among 29 patients, 19 received HSCT for hematologic malignancy, 8 for non-malignant hematologic disorders, and 2 for metastatic solid tumors. Twenty-five patients (86%) showed 1 or more patterns of acute and organizing lung injury. Sixty-two percent had microvascular sclerosis, with venous involvement noted in most cases and not correlating with clinical history of pulmonary hypertension, clinical transplant-associated thrombotic microangiopathy, irradiation, or graft-versus-host disease. Features suggestive of graft-versus-host-disease were uncommon: 6 patients had lymphocytic bronchiolitis, and only 2 patients had evidence of bronchiolitis obliterans (both clinically unexpected), both with a mismatched unrelated donor transplant.

CONCLUSIONS

Acute and subacute alveolar injury (diffuse alveolar damage or organizing pneumonia) is common in pediatric patients who died following HSCT and is difficult to assign to a specific etiology. Microvascular sclerosis was frequent and did not correlate with a single distinct clinical feature.

Pulmonary Hypertension and Cancer: Etiology, Diagnosis, and Management

OPINION STATEMENT

Pulmonary hypertension is caused by cancer and its therapeutic agents including chemotherapy, radiotherapy, and even the targeted therapies. Ironically, some of the cancer therapies that cause one type of pulmonary hypertension (PH) could potentially be employed in the treatment of another PH type. Greater awareness on the role of cancer therapeutic agents in causing PH is required. Conversely, since PH is mostly incurable, the potential role of some of these cancer therapeutic agents in the cure of PH should be recognized. In short, the relationship between cancer, cancer therapy, and PH is an interesting one requiring further attention, education, and research.

A case of pulmonary arterial hypertension associated with adult hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is an aggressive, life-threatening syndrome of excessive immune activation. Presentation is most common among the pediatric population, and cases in adults are rare. The number of nonhematologic presentations described in relation to HLH has been growing. We present a case involving a woman who developed HLH after autologous stem cell transplantation for mantle cell lymphoma. Months later, she received a diagnosis of pulmonary arterial hypertension (PAH) while undergoing treatment for her HLH. To our knowledge, PAH associated with adult HLH has only been described in the literature once before. PAH may now be a potential differential diagnosis for patients with HLH who present with respiratory symptoms.

Chemotherapy-induced pulmonary hypertension: role of alkylating agents

Pulmonary veno-occlusive disease (PVOD) is an uncommon form of pulmonary hypertension (PH) characterized by progressive obstruction of small pulmonary veins and a dismal prognosis. Limited case series have reported a possible association between different chemotherapeutic agents and PVOD. We evaluated the relationship between chemotherapeutic agents and PVOD. Cases of chemotherapy-induced PVOD from the French PH network and literature were reviewed. Consequences of chemotherapy exposure on the pulmonary vasculature and hemodynamics were investigated in three different animal models (mouse, rat, and rabbit). Thirty-seven cases of chemotherapy-associated PVOD were identified in the French PH network and systematic literature analysis. Exposure to alkylating agents was observed in 83.8% of cases, mostly represented by cyclophosphamide (43.2%). In three different animal models, cyclophosphamide was able to induce PH on the basis of hemodynamic, morphological, and biological parameters. In these models, histopathological assessment confirmed significant pulmonary venous involvement highly suggestive of PVOD. Together, clinical data and animal models demonstrated a plausible cause-effect relationship between alkylating agents and PVOD. Clinicians should be aware of this uncommon, but severe, pulmonary vascular complication of alkylating agents.

Pulmonary hypertension after hematopoietic stem cell transplantation

Pulmonary hypertension (PH) is a potentially fatal complication of hematopoietic stem cell transplantation (HSCT). Given its nonspecific clinical presentation, it is likely that this clinical entity is underdiagnosed after HSCT. Data describing the incidence, risk factors, and etiology of PH in HSCT recipients are minimal. Physicians caring for HSCT recipients should be aware of this severe post-transplant complication because timely diagnosis and treatment may allow improved clinical outcomes. We summarize the pathophysiology, clinical presentation, diagnosis, and management of PH in HSCT recipients.

Pulmonary arterial hypertension in pediatric patients with hematopoietic stem cell transplant-associated thrombotic microangiopathy

Pulmonary arterial hypertension (PAH) is rarely included in the differential diagnosis of cardiorespiratory failure after pediatric hematopoietic stem cell transplant (HSCT) as the clinical presentation is nonspecific and may mimic other etiologies. The pathogenesis of PAH in HSCT is poorly understood and the diagnosis requires a high degree of suspicion. We describe 5 children diagnosed with PAH after allogeneic HSCT. All 5 patients had prolonged clinical signs of transplantation-associated thrombotic microangiopathy (TA-TMA) when they presented with hypoxemic respiratory failure and evidence of PAH. Four of the 5 patients had echocardiographic evidence of PAH, and 1 patient was diagnosed with PAH only on autopsy. PAH was diagnosed a median of 76 days (range, 56-101 days) after a diagnosis of TA-TMA. Despite aggressive medical management, including inhaled nitric oxide, 4 of the 5 patients died. One patient recovered from PAH after 11 months of sildenafil therapy. Three of the 4 deceased patients had an autopsy performed, demonstrating severe pulmonary vascular disease consistent with TA-TMA and severe PAH. We conclude that TA-TMA can be associated with significant pulmonary vascular injury presenting as hypoxemic respiratory failure with PAH after HSCT. Pediatric patients with unexplained hypoxemia after HSCT should be evaluated for both transplantation complications, TA-TMA and PAH, accordingly.

What Has Been Learned from Postmortem Studies?

Infectious and noninfectious pulmonary diseases are commonly found on postmortem autopsy studies in patients with hematological malignancy. Despite the technological advances in diagnostic testing and imaging modalities, obtaining an accurate clinical diagnosis remains difficult and often not possible until autopsy. Major diagnostic discrepancies between clinical premortem diagnoses and postmortem autopsy findings have been reported in these patients. The most common missed diagnoses are due to opportunistic infections and cardiopulmonary complications. These findings underscore the importance of enhanced surveillance, monitoring and treatment of infections and cardiopulmonary disorders in these patients. Autopsies remain important in determining an accurate cause of death and for improved understanding of diagnostic deficiencies, as well as for medical education and quality assurance.

Pulmonary hypertension associated with bone marrow transplantation

Bone marrow transplantation (BMT) is one of the promising methods of treatment of hematologic malignancy. However, it has a variety of complications since it involves fatal doses of anti-cancer drugs and radiation during the conditioning period. Among the various complications of BMT, pulmonary hypertension is rare and its pathogenesis is poorly understood. A 35-year-old female with acute myeloid leukemia (AML) presented with pulmonary hypertension after BMT. Although she exhibited severe dyspnea on admission, her general condition markedly improved after oxygen therapy and treatment with warfarin and beraprost sodium. Her pulmonary hypertension was diagnosed as pulmonary arterial hypertension (PAH) related to BMT. Although PAH has only rarely been reported as a complication of BMT, we present here for the first time an adult patient with PAH associated with BMT who exhibited marked improvement with medical treatment. This case indicates that attention needs to be paid to the clinical symptoms and physical findings of PAH as a complication of BMT.

Bronchiolitis obliterans syndrome (BOS), bronchiolitis obliterans organizing pneumonia (BOOP), and other late-onset noninfectious pulmonary complications following allogeneic hematopoietic stem cell transplantation

Pulmonary dysfunction is a significant complication following allogeneic hematopoietic stem cell transplantation (HSCT), and is associated with significant morbidity and mortality. Effective antimicrobial prophylaxis and treatment strategies have increased the incidence of noninfectious lung injury, which can occur in the early posttransplant period or in the months and years that follow. Late-onset noninfectious pulmonary complications are frequently encountered, but diagnostic criteria and terminology for these disorders can be confusing and therapeutic approaches are suboptimal. As a consequence, inaccurate diagnosis of these conditions may hamper the appropriate data collection, enrollment into clinical trials, and appropriate patient care. The purpose of this review is to clarify the pathogenesis and diagnostic criteria of representative conditions, such as bronchiolitis obliterans syndrome and bronchiolitis obliterans organizing pneumonia, and to discuss the appropriate diagnostic strategies and treatment options.

Pulmonary veno-occlusive disease following hematopoietic stem cell transplantation: a rare model of endothelial dysfunction

Veno-occlusive disease is among the most serious complications following hematopoietic stem cell transplantation. While hepatic veno-occlusive disease occurs more commonly, the pulmonary variant remains quite rare and often goes unrecognized antemortem. Endothelial damage may represent the pathophysiologic foundation of these clinical syndromes. Recent advances in the treatment of hepatic veno-occlusive disease may have application to its pulmonary counterpart.

Chronic lung disease after hematopoietic stem cell transplantation

Tens of thousands of patients undergo hematopoietic stem cell transplantation (HSCT) each year, mainly for hematologic disorders. In addition to the underlying diseases, the chemotherapy and radiation therapy that HSCT recipients receive can result in damage to multiple organ systems. Pulmonary complications develop in 30% to 60% of HSCT recipients. With the widespread use of prophylaxis for certain infections, the spectrum of pulmonary complications after HSCT has shifted from more infectious to noninfectious complications. This article reviews some of the noninfectious, chronic pulmonary complications.

Pulmonary Complications in Adult Blood and Marrow Transplant Recipients

STUDY OBJECTIVE

To describe the pulmonary findings at autopsy of blood and bone marrow transplant (BMT) recipients.

DESIGN

Retrospective.

SETTING

An academic medical center.

PATIENTS

Seventy-one deceased adult BMT recipients.

INTERVENTIONS

None.

MEASUREMENTS

Antemortem and postmortem pulmonary findings.

RESULTS

The transplants were allogeneic in 39 patients (55%), with a peripheral stem cell source in 43 patients (61%). Death occurred at a median of 1.30 months after transplant. Ninety-six pulmonary complications were noted in 63 patients (89%): 27 infectious (bacterial bronchopneumonia, n = 13; pulmonary aspergillosis, n = 11; cytomegalovirus pneumonia, n = 2; and Candida bronchopneumonia, n = 1) and 69 noninfectious (diffuse alveolar damage, n = 35; diffuse alveolar hemorrhage [DAH], n = 10; amyloidosis, n = 9; pulmonary embolism, n = 5; lymphoma/leukemia, n = 4; bronchiolitis obliterans, n = 2; bronchiolitis obliterans organizing pneumonia, n = 1; pulmonary alveolar proteinosis, n = 1; aspiration pneumonia, n = 1; and acute and organizing pneumonia, n = 1). Twenty-seven of the 96 complications (28%) were diagnosed antemortem. Infectious complications were more likely to be diagnosed antemortem compared to noninfectious complications (48% vs 20%, p = 0.006). Six of the 13 patients with bronchopneumonia (46%), 5 of the 11 patients with pulmonary aspergillosis (45%), and 7 of the 8 patients with DAH (88%) at autopsy were not receiving treatment for these conditions at the time of death. Ten patients being treated for suspected pulmonary aspergillosis, 7 patients treated for suspected pulmonary cytomegalovirus infection, 22 patients treated for suspected bacterial pneumonia, 2 patients treated for suspected Pneumocystis carinii pneumonia, and 12 patients treated for DAH at the time of death had no evidence of these conditions at autopsy. The most common immediate cause of death was respiratory failure (n = 37, 52%).

CONCLUSIONS

Pulmonary complications, the majority not diagnosed antemortem, are the most common cause of death in BMT recipients. As the result of underdiagnosis, BMT recipients may not receive appropriate therapy for potentially treatable pulmonary complications.

Thrombotic thrombocytopenic purpura-hemolytic uremic syndrome following allogeneic HPC transplantation: a diagnostic dilemma

BACKGROUND

Thrombotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS) has been described as a specific sequela of allogeneic HPC transplantation (HPCT). Nevertheless, because multiple transplant-related sequela can cause the characteristic clinical features of TTP-HUS, the diagnosis is difficult.

STUDY DESIGN AND METHODS

All English-language articles describing patients with TTP-HUS following HPCT were identified. Articles reporting five or more total patients, including at least one patient diagnosed with TTP-HUS following allogeneic HPCT, were reviewed. All articles describing autopsies of patients diagnosed with TTP-HUS following allogeneic HPCT were also reviewed.

RESULTS

Thirty-five articles reporting 5 or more total patients described 447 patients diagnosed with TTP-HUS following allogeneic HPCT. The frequency of diagnosis of TTP-HUS following allogeneic HPCT varied by 125-fold (0.5%-63.6%). Twenty-eight different sets of diagnostic criteria were described in the 35 articles; 25 articles included both RBC fragmentation and increased serum LDH. Many risk factors described as correlating with the diagnosis of TTP-HUS also predict greater risk for multiple transplant-related complications. Benefit of plasma exchange treatment could not be documented. Survival information was reported for 379 patients, 232 (61%) died, and reported mortality rates varied from 0 to 100 percent. Autopsies have been reported for 35 patients who were diagnosed with TTP-HUS following allogeneic HPCT; none had systemic thrombotic microangiopathy, the diagnostic abnormality of TTP-HUS; and infection (19 patients) was the most commonly reported cause of death.

CONCLUSIONS

The clinical features of TTP-HUS following allogeneic HPCT may be caused by common transplant-related complications; the benefit from plasma exchange treatment is uncertain.

Pulmonary veno-occlusive disease after autologous bone marrow transplant in a child with stage IV neuroblastoma: case report and literature review

Pulmonary veno-occlusive disease (PVOD) is a rare, almost universally fatal complication of chemotherapy and bone marrow transplantation with few treatment options. A 19-month-old boy with stage 4 neuroblastoma with fatal PVOD following high-dose chemotherapy with autologous peripheral blood stem cell rescue is described here. A comprehensive literature review revealed 40 case reports of PVOD in oncology patients. Various therapeutic modalities were attempted, with four survivors. PVOD should be considered in patients with dyspnea and cardiomegaly. Less invasive diagnostic methods and more effective therapies are needed.

Thrombotic microangiopathy in blood and marrow transplant patients receiving tacrolimus or cyclosporine A

BACKGROUND

Cyclosporine A (CSA) and tacrolimus (FK-506) are both associated with thrombotic microangiopathy (TMA) in allogeneic BMT recipients, although it is not known which drug is more likely to cause the syndrome. The optimal treatment of BMT-associated TMA is also not known.

STUDY DESIGN AND METHODS

To estimate the risks, predisposing factors, and outcomes of TMA, data were analyzed from two cohorts of BMT patients who had received CSA or FK-506 in our institution with the same clinical definition for TMA. TMA was diagnosed in 11 of 55 patients (CSA, 3 of 24; FK-506, 8 of 31).

RESULTS

The daily risk of developing TMA was 0.12 percent for patients receiving CSA and 0.26 percent for those receiving FK-506 (p = 0.16, chi-square). Among patients receiving FK-506, sibling donor BMT recipients were as likely to develop TMA as matched unrelated donor recipients. Serum CSA and FK-506 concentrations were not elevated above the therapeutic range in most patients with TMA. The blood urea nitrogen to serum creatinine ratio was elevated in patients with TMA. Despite daily plasmapheresis, 9 of 11 patients died without resolution of TMA; however, the causes of death were multifactorial, including GVHD. Histologic evidence for TMA was absent in 1 patient who died with persistent clinical signs attributed to microangiopathy.

CONCLUSIONS

In this study, a high incidence of TMA was found in patients receiving either CSA or FK-506 following BMT, with uniform diagnostic criteria and strict monitoring. Neither drug showed elevated levels in most patients with TMA. Plasmapheresis was unsuccessful in reversing most cases of TMA.

Pulmonary hypertension associated with pulmonary occlusive vasculopathy after allogeneic bone marrow transplantation

BACKGROUND

Pulmonary vasculature abnormalities, including pulmonary veno-occlusive disease, have been demonstrated in marrow allograft recipients. However, it is often difficult to make a correct diagnosis of pulmonary lesions.

METHODS

An open lung biopsy was performed on a patient who developed severe pulmonary hypertension after bone marrow transplantation for T-cell lymphoma.

RESULTS

An open lung biopsy specimen demonstrated pulmonary arterial occlusion due to intimal fibrosis and veno-occlusion. The most striking alteration was partial to complete occlusion of the small arteries by fibrous proliferation of the intima.

CONCLUSION

High-dose preparative chemotherapy and radiation before transplantation are thought to have contributed to the development of vasculopathy in this patient, because arterial occlusion by intimal fibrosis and atypical veno-occlusion are often associated with lung injury due to chemoradiation. An open lung biopsy is essential for diagnosing pulmonary vascular disease presenting signs compatible with posttransplantation pulmonary hypertension.