Pulmonary complications following hematopoietic stem cell transplantation: diagnostic approaches

Pulmonary complications are a significant cause of morbidity and mortality in hematopoietic stem cell transplant recipients. Pulmonary infiltrates in such patients pose a major challenge for clinicians because of the wide differential diagnosis of infectious and noninfectious conditions. It is rare for the diagnosis to be made by chest radiograph, and commonly these patients will need further invasive and noninvasive studies to confirm the etiology of the pulmonary infiltrates. This review describes the role of the different diagnostic tools available to reach a diagnosis in a timely manner in this patient population.

Peak expiratory flow with or without a brief postinspiratory pause

BACKGROUND

The duration of postinspiratory pause prior to forced expiration may significantly influence the peak expiratory flow (PEF) measured during maximal forceful expirations. In comparison with maneuvers without a postinspiratory pause, maneuvers with 4 to 6-s pause at total lung capacity (TLC) result in decreased PEF values. The extent to which brief pauses (< 2 s) similarly affect PEF values is unknown.

METHODS

Thirty-six healthy volunteers (mean [+/-SD] age, 35 +/- 8 years; 18 men) performed a series of maximal forceful expirations with two different types of maneuvers. One maneuver (NP) included no inspiratory pause at TLC prior to forceful expiration, whereas the second (P) included a brief pause (< or = 2 s). The speed of inhalation to TLC was rapid and similar for both maneuvers. The highest PEF for each maneuver was used for analysis.

RESULTS

The maximal PEF did not differ (p > 0.05) between the P and NP maneuvers (7.78 +/- 1.45 vs 7.83 +/- 1.45 L/s, respectively). Comparison of the intermaneuver differences showed a bias of 0.05 L/s and 95% confidence interval in the range of -0.9 to 1.0 L/s.

CONCLUSIONS

Forceful expiratory maneuvers with or without postinspiratory pauses of < or = 2 s produce identical maximal PEF values and, therefore, can be used interchangeably for the spirometric measurement of PEF in healthy subjects.

Critical Care Aspects of Alcohol Abuse

The authors reviewed MEDLINE and references of major articles in the published literature over the last 30 years regarding the complications of alcohol abuse and discuss the critical care aspects of alcohol abuse. This article discusses the severe medical conditions associated with alcohol abuse that lead to admission to the medical intensive care unit. The clinical manifestations, pathophysiology, diagnostic studies, and management of these conditions are discussed in detail.

Outcome and prognostic factors of hematopoietic stem cell transplantation recipients admitted to a medical ICU

OBJECTIVE

To assess the outcome of adult hematopoietic stem cell transplantation (HSCT) recipients who were admitted to a medical ICU (MICU), and to identify the measurable predictors of their MICU outcome.

DESIGN

Retrospective chart review study.

SETTING

MICU in a tertiary care, university-affiliated medical center with a comprehensive cancer program.

PATIENTS

Consecutive adult HSCT recipients admitted to the MICU between January 1998 and June 2001.

MEASUREMENTS AND MAIN RESULTS

Eighty-five patients were admitted to the MICU, representing 11.4% of patients who had undergone HSCT during the study period. The mean (+/- SD) age at MICU admission was 46.6 +/- 11.4 years (women, 67%; men, 33%). Forty-five patients (53%) underwent allogeneic HSCT, and 40 patients (47%) underwent autologous HSCT. Fifty-one patients (60%) required mechanical ventilation (MV). Fifty-two patients (61%) survived their MICU stay, and 35 patients (41%) were discharged alive from the hospital. The long-term survival rate (ie, > 6 months) in this cohort was 28%. Nineteen mechanically ventilated patients (37%) survived their MICU stay, and 33 patients (97%) survived who did not require MV (p < 0.01). The independent predictors of poor outcome during the MICU stay were elevated serum lactate level on admission to the MICU, the need for MV, and the presence of more than two organ systems that failed.

CONCLUSIONS

The study showed short-term and long-term survival rates among adult HSCT recipients who had been admitted to MICU that were higher than those previously reported. While there were no absolute predictors of mortality, patients with higher MICU admission serum lactate levels, those requiring MV, or those developing more than two organ system failures had poor MICU outcomes.

Surgical lung biopsy in patients with hematological malignancy or hematopoietic stem cell transplantation and unexplained pulmonary infiltrates: improved outcome with specific diagnosis

Using a retrospective review of medical records, we sought the findings of surgical lung biopsy (SLB) in patients with hematological malignancy or hematopoietic stem cell transplantation (HSCT) and unexplained pulmonary infiltrates and to determine the impact of this procedure on management and outcome of these patients. Sixty-two patients who underwent SLB were evaluated; 31 patients had underlying hematological malignancy and 31 patients were HSCT recipients; 58% of whom underwent allogeneic HSCT. Thirty-three patients (53%) had focal infiltrates on chest CT scan while 29 (47%) had diffuse infiltrates. Thirteen patients were mechanically ventilated prior to SLB, and 27 (43%) were neutropenic. There were 66 diagnoses in the 62 patients, 44 (67%) were specific and 22 (33%) were nonspecific. The most common specific diagnoses were infection (29%), malignancy (27%), and inflammatory conditions (11%). Aspergillosis was the most common diagnosis of all biopsies (21%). SLB led to a change in therapy in 40% of patients and was associated with complications in 7 patients (11%). Specific diagnosis was more likely to lead to a change in therapy (48% vs. 27%, P = 0.06) and was associated with a lower mortality when compared to a nonspecific finding (30% vs. 59%, P = 0.02). Nonspecific diagnosis, on the other hand, was seen more in patients on mechanical ventilation prior to SLB compared to those off mechanical ventilation (69% vs. 27%, P = 0.02). SLB provides a specific diagnosis in the majority of patients with hematologic malignancy or HSCT recipients and unexplained pulmonary infiltrates. Specific diagnosis is more likely to lead to a change in therapy and is associated with a better outcome.

Clinical significance of lower respiratory tract Aspergillus culture in elderly hospitalized patients

In order to evaluate the clinical significance of Aspergillus-positive culture results from the lower respiratory tract specimens of elderly hospitalized patients, and to identify the clinical variables that differentiate between colonization and infection with Aspergillus spp. in this patient population, a retrospective study was conducted. The records of 66 elderly patients whose lower respiratory tract specimens yielded Aspergillus spp. between January 1995 and July 2000 were examined. The majority of the patients ( n=61) were determined to be colonized with Aspergillus spp., and serious lung infection due to Aspergillus spp. was rare. Clinical, radiological, and microbiological data did not help differentiate between infection and colonization.

Increased Exhaled Nitric Oxide Following Autologous Peripheral Hematopoietic Stem-Cell Transplantation

BACKGROUND

Increased production of nitric oxide (NO) and oxidative stress following bone marrow transplantation may play a role in the pathogenesis of idiopathic pneumonia syndrome (IPS). We hypothesize that patients who received high-dose chemotherapy followed by autologous peripheral hematopoietic stem-cell transplantation (APHSCT) have increased exhaled NO.

METHOD

We measured exhaled lower respiratory tract NO concentration with a chemiluminescent NO analyzer during a slow vital capacity maneuver against a positive pressure of 16 cm H(2)O at an expiratory flow rate of 50 mL/s in 20 female patients who received high-dose chemotherapy (cyclophosphamide, carmustine, and cisplatin) followed by APHSCT for the treatment of stage III or IV breast carcinoma. Pulmonary function tests were performed, and exhaled NO measurements and clinical and laboratory data were obtained before transplantation and at every 6-week visit after transplantation for 24 weeks.

RESULTS

All study patients had evidence of IPS with dyspnea and reduction in diffusion capacity of the lung for carbon monoxide (DLCO). Lower respiratory tract exhaled NO was significantly higher after APHSCT and during the 6 months of follow-up. Mean (+/- SD) exhaled NO increased from (mean +/- SD) 12.54 +/- 1.32 parts per billion (ppb) before APHSCT to 21.26 +/- 1.94 ppb at 6 weeks (p = 0.099), 21.26 +/- 1.94 ppb (p = 0.006) at 12 weeks, 24.62 +/- 2.55 ppb (p = 0.012) at 18 weeks, and 25.28 +/- 3.31 ppb (p = 0.013) at 24 weeks (all p values were compared to baseline). There was a strong negative correlation between DLCO and exhaled NO (regression coefficient - 0.60, p = 0.01).

CONCLUSION

Lower respiratory tract concentration of exhaled NO is significantly increased following APHSCT and correlates with reduction in DLCO. Increase in lower respiratory tract concentration of NO is a potential marker of IPS.

Invasive pulmonary aspergillosis following bone marrow transplantation: risk factors and diagnostic aspect

AIM

To describe the clinical features and diagnostic aspects of invasive pulmonary aspergillosis (IPA) following bone marrow transplantation (BMT).

METHODS

Retrospective review of the medical records of all BMT recipients in whom Aspergillus spp. were isolated from the lower respiratory tract. The diagnosis of IPA was definite when the fungus was demonstrated by histological examination or culture of lung tissue obtained by biopsy or autopsy. The diagnosis was probable when Aspergillus spp. were isolated by culture of BAL or sputum, with compatible clinical and radiologic picture.

RESULTS

There were 27 patients with IPA post-BMT (81% allo versus 19% auto). The diagnosis was made median of 20-week posttransplanttation: 67% had GVHD, 59% were on immunosuppressive therapy and 89% were on corticosteroids. Only 11% had severe neutropenia (ANC < 500). The clinical symptoms were nonspecific, and radiologically the commonest manifestations were nodules with or without cavitation 34%. The diagnosis of IPA was definite in 11 patients (41%): 6 by open lung biopsy, 1 by CT-guided biopsy, 1 by BAL and brain biopsy and 3 by autopsy. The diagnosis was probable in 16 (59%): 6 by BAL, 7 by sputum culture and 3 both. Aspergillus spp. were recovered from 10/17 (59%) patients who had BAL and 10/15 (67%) who had sputum culture. 25 patients were treated with antifungal agents (19 amphtericin B alone, 4 amphotericin B and itraconacole, 2 variconazole). 16/27 (59%) died a median of 15.5 days after the diagnosis of IPA. 5 had documented evidence of disseminated disease, most commonly to brain.

CONCLUSION

IPA is an important problem following BMT. Allogeneric transplant, GVHD, immuno-suppressive and corticosteroid therapy are the main risk factors. BAL and sputum examination are helpful in making the diagnosis in the appropriate clinical setting. Although the mortality associated with IPA remains high, however it is lower than what was previously reported.

The clinical spectrum of pulmonary aspergillosis

Aspergillus is a ubiquitous fungus that causes a variety of clinical syndromes in the lung, ranging from aspergilloma in patients with lung cavities, to chronic necrotizing aspergillosis in those who are mildly immunocompromised or have chronic lung disease. Invasive pulmonary aspergillosis (IPA) is a severe and commonly fatal disease that is seen in immunocompromised patients, while allergic bronchopulmonary aspergillosis is a hypersensitivity reaction to Aspergillus antigens that mainly affects patients with asthma. In light of the increasing risk factors leading to IPA, such as organ transplantation and immunosuppressive therapy, and recent advances in the diagnosis and treatment of Aspergillus-related lung diseases, it is essential for clinicians to be familiar with the clinical presentation, diagnostic methods, and approach to management of the spectrum of pulmonary aspergillosis.

Flexible bronchoscopy in the diagnosis of pulmonary infiltrates following autologous peripheral stem cell transplantation for advanced breast cancer

Flexible bronchoscopy is an important tool in the diagnosis of pulmonary complications following bone marrow transplantation. However, the value of this procedure in autologous peripheral stem cell transplant (APSCT) recipients with pulmonary complications is not well defined. We retrospectively evaluated the diagnostic yield of 27 consecutive bronchoscopies done on 23 APSCT recipients following high-dose chemotherapy for breast cancer. FB resulted in a positive diagnosis in 16 cases (59%). Broncheoalveolar lavage (BAL) was performed on all patients, and transbronchial biopsies (TBB) were carried out in 14. TBB were diagnostic in 10 (71%), with pulmonary drug toxicity as the most common finding (n = 8), followed by metastatic breast cancer (n = 2). BAL was diagnostic in six (22%): bacterial pneumonia (n = 3), aspergillosis (n = 2), Pneumocystis carinii pneumonia (n = 1) and Influenza B (n = 1). The procedure was well tolerated with no major complications except a small pneumothorax in one patient that did not require chest tube insertion. In conclusion, flexible bronchoscopy is a useful tool in the evaluation of pulmonary complications following APSCT for breast cancer. TBB can be done safely with relatively high diagnostic yield. Pulmonary drug toxicity is the most common pathological finding.

Noninvasive monitoring of oxygen and carbon dioxide

Pulse oximetry and capnography are widely used in clinical practice. They provide quick and noninvasive methods to estimate arterial oxygen saturation and carbon dioxide tension in different situations including emergency departments, intensive care units, and during procedures. This article reviews the principles of surgery, accuracy, limitations, and clinical applications of these instruments.

Pleural fluid findings in patients with the acquired immunodeficiency syndrome: correlation with concomitant pulmonary disease

BACKGROUND

We sought to define the spectrum of conditions associated with pleural effusion (PE) in patients with the acquired immunodeficiency syndrome (AIDS) who submitted to diagnostic thoracentesis.

METHODS

The medical records of patients with human immunodeficiency virus (HIV) infection and PE studied by thoracentesis over a 5-year period, were reviewed for demographics, clinical presentation, concomitant illnesses, pleural fluid analysis, management, and outcome.

RESULTS

Thoracentesis was done in 30 patients, 24 men and 6 women, with an overall mean age of 36 +/- 9 years. Mean CD4 cell count was 157 +/- 249/mm3. The cause of the PE was infectious in 21 (70%) and noninfectious in 9 (30%). Bacterial pneumonia was the most common cause of PE (57%). Streptococcus pneumoniae and Staphylococcus aureus were the major organisms recovered. Mycobacterial infections were present in 3 patients, and Nocardia sp was isolated from 1 patient. Non-Hodgkin's lymphoma (5 cases) was the leading noninfectious cause of PE, followed by Kaposi's sarcoma (3 cases) and adenocarcinoma of the lung (1 case). Twelve of the 30 patients died during hospitalization.

CONCLUSION

Pleural effusion is an important problem in patients with advanced HIV infection. It is most frequently associated with bacterial pneumonia. Cytologic and microbiologic examination of the pleural fluid is helpful in determining the cause of PE in this patient population.

Life-threatening "round pneumonia"

Round pneumonia is a rare manifestation of lower respiratory tract infection in adults. Previous reports emphasize that this entity is typically a mild, easily treatable illness that often masquerades radiographically as a neoplasm. We present two cases of round pneumonia, in patients with abnormal immunity, that progressed rapidly to life-threatening septic shock and respiratory failure.

Cardiogenic shock due to huge right atrial thrombus

An unusual case is reported of right atrial thrombus associated with cardiogenic shock. The role of two-dimensional echocardiography in detection of blood clots is highlighted.