A survey of training in pediatric flexible bronchoscopy

OBJECTIVE

There is currently no evidence-based method for defining competency in pediatric flexible bronchoscopy (FB). Based on expert opinion, guidelines using numbers of procedures have been published in defining competency for pediatric FB. The purpose of this study was to formally survey the opinion of USA pediatric pulmonology training directors about the assessment of competency and training experiences in pediatric FB in their programs.

METHODS

An Internet-based Survey Monkey™ of the Pediatric Pulmonary Training Directors Association (PEPTDA) was administered 10/12/10 through 11/1/10 with a supplemental survey 6/1/11-6/30/11.

RESULTS

This survey of US pediatric pulmonology training directors about competency and training in pediatric FB showed that a majority (86%) felt there was a minimum threshold of procedures for developing competency that could be defined, with a median of 50 and an average of 56.4 (SD = 33.0). The actual number of FBs performed by fellows during their 3-year fellowship averaged 89.4 (SD = 45.3) with a range of 10-200. The survey also revealed a variety of teaching techniques used for FB, including simulation technology. Finally many differences were reported in skill assessment, locations for performance of FB, and the range of underlying indications and patient populations. The apprenticeship model is the predominant method of learning FB in the surveyed programs.

CONCLUSIONS

A majority of US pediatric pulmonology training directors felt that a minimum number of procedures could be defined for developing competency in pediatric FB. There was variability in the numbers of procedures performed, training techniques and assessment, and application of FB. This survey represents an initial step in assessing training and defining competency in pediatric FB.

Lung transplantation after allogeneic marrow transplantation in pediatric patients: the Memorial Sloan-Kettering experience

BACKGROUND

Chronic lung disease and pulmonary failure are complications that can occur after bone marrow transplantation (BMT) and are associated with severe morbidity and mortality.

METHODS

We report on four patients who developed chronic, progressive, and irreversible lung disease 1 to 3 years after allogeneic BMT in childhood. These patients had chronic graft-versus-host disease (n=3) or radiation-related pulmonary fibrosis (n=1). Three patients underwent double lung transplants and one patient underwent a single lung transplant 2 to 14 years after BMT.

RESULTS

All four patients tolerated the lung transplantation procedure well and showed significant clinical improvement with normalization of pulmonary function tests by 1 year posttransplant. One patient died from infectious complications 3 years after lung transplantation, and one patient died after chronic rejection of the transplanted lungs 6 years posttransplant. Two patients remain alive without significant respiratory impairment 2 and 7 years after lung transplantation.

CONCLUSION

We conclude that lung transplantation offers a viable therapeutic option for patients who develop respiratory failure secondary to BMT.

Hematologic abnormalities in children and young adults receiving tacrolimus-based immunosuppression following cardiothoracic transplantation

To define the incidence, course, and etiology of hematologic abnormalities in children on tacrolimus-based immunosuppression, we reviewed records of 106 transplant patients (70 heart, 16 heart and lung, 20 double lung), 0-21 yr of age, who were transplanted at the Children's Hospital of Pittsburgh from 1989 to 1997. Fifty-four of the 106 patients (51%) developed 65 abnormal hematologic episodes (32 anemia, nine neutropenia, nine thrombocytopenia, 15 simultaneous anemia and neutropenia with or without thrombocytopenia). Common etiologies included: infections, post-transplant lymphoproliferative disease, and medications. Eleven episodes (seven anemia, one neutropenia, and three simultaneous anemia and neutropenia) had unclear etiologies and process of elimination suggested an association with tacrolimus. Interventions included filgrastim (effective in 15 of 15 patients, with resolution of neutropenia in a median of 5 days) and epoetin alfa (effective in five of 16 patients, including four of four patients with anemia possibly related to tacrolimus). Five patients (two with neutropenia and three with simultaneous neutropenia and anemia) were switched to cyclosporin A (CsA); rapid resolution occurred in four of the five patients, suggesting a possible association of the hematologic abnormalities with tacrolimus. In summary, hematologic abnormalities are common in children on tacrolimus-based immunosuppression. Most of these hematologic abnormalities are caused by common etiologies; however, a sub-population exists where tacrolimus may be the etiologic agent. Anemia and neutropenia respond to treatment with epoetin alfa and filgrastim. After thorough investigation, a trial switch to CsA may be warranted.

Recurrent medulloblastoma following pediatric double-lung transplant

We report a case of recurrent medulloblastoma following successful pediatric double-lung transplant for chemotherapy-induced pulmonary fibrosis. The patient had an apparent 10-year malignancy-free period prior to the transplant. This case demonstrates a potential complication of lung transplantation in individuals with prior malignancies, and questions whether patients with a history of medulloblastoma are suitable candidates for lung transplantation.

Airway complications following pediatric lung and heart-lung transplantation

Obstruction at the airway anastomosis is a recognized complication of adult heart-lung transplantation (HLT) and lung transplantation (LT). Data for pediatric transplantation have been scarce. We reviewed our experience in pediatric HLT and LT to determine the frequency of airway complications and to document the therapeutic modalities used for their treatment. Fifty-three patients (median age: 13.8 yr; range: 1.3 to 28.2 yr) underwent HLT (n = 25), SLT (n = 3), DLT (n = 25), or repeat DLT (n = 3) and survived for more than 72 h. Major anastomotic airway complications requiring intervention affected one of the 25 HLT (4%) and seven of the 28 LT (SLT + DLT) patients (25%) (p = 0.05). Four patients with granulation tissue occluding the airway were treated with forceps resection, laser ablation, or balloon dilatation. Three patients with fibrotic strictures received silicone stents, laser ablation, or balloon dilatation. Two patients with bronchomalacia or diffuse stricture below the anastomosis underwent metal stent placement. Five of seven patients who were treated for anastomotic complications had satisfactory relief of airway obstruction. As compared with previously studied adults, pediatric heart-lung transplant recipients had the same or a lower frequency, and pediatric lung transplant recipients had a higher frequency of major anastomotic airway complications. A variety of treatment modalities were necessary to achieve adequate relief of airway obstruction.

Posttransplantation lymphoproliferative disorders in pediatric thoracic organ recipients

OBJECTIVE

To determine the frequency, predisposing factors, clinical presentation, and outcome of posttransplantation lymphoproliferative disorders (PTLDs) in pediatric thoracic organ transplant recipients.

METHODS

Retrospective review of the medical records of all 120 children who survived longer than 1 month after thoracic organ transplantation at our center.

RESULTS

PTLD was diagnosed in 14 patients (11.7%), including 7.7% of heart and 19.5% of heart-lung/lung recipients. Presentation of PTLD was variable, ranging from asymptomatic lung nodules on chest radiograph to diffuse multiorgan failure. Treatment with a reduction of immunosuppression and antiviral therapy resulted in resolution of PTLD in eight patients. Eight patients died. PTLD contributed to death in five. No patient seropositive for Epstein-Barr virus (EBV) before transplantation had PTLD. There was a significant association between primary EBV infection after transplantation and the presence of PTLD.

CONCLUSIONS

PTLD occurs with greater frequency in pediatric thoracic organ transplant recipients than in the adult transplant population. Primary EBV infection after transplantation is the major risk factor for the development of PTLD. Patients in whom primary EBV infection develops after transplantation should be managed with a reduction in immunosuppression and with heightened surveillance for the development of PTLD.

New-onset diabetes mellitus in pediatric thoracic organ recipients receiving tacrolimus-based immunosuppression

BACKGROUND

Tacrolimus has a negative effect on the pancreatic beta islet cell, and both glucose intolerance and diabetes mellitus are well-recognized complications of tacrolimus-based immunosuppression among adult solid organ transplant recipients.

METHODS

To determine the association between tacrolimus and new-onset diabetes mellitus in childhood, we reviewed data on 78 pediatric heart and heart-lung/lung recipients receiving tacrolimus-based immunosuppression. Trough tacrolimus levels, fasting and random blood glucose levels, and corticosteroid requirements were reviewed. Diabetes was defined as glucose intolerance requiring long-term insulin treatment more than 30 days after transplantation.

RESULTS

No patient had diabetes before introduction of tacrolimus. In heart-lung/lung recipients, 12 of 28 (43%) had development of diabetes at a median follow-up of 7 months (range 1 to 39). In this group diabetes developed in three of eight (38%) patients with cystic fibrosis and nine of 20 (45%) without (p = NS). In contrast, only two of 50 (4%) heart transplant recipients had development of diabetes. Of the 14 patients with diabetes, 10 had development of diabetes during augmentation of immunosuppression with pulsed corticosteroids. Tacrolimus trough levels were significantly lower in heart compared with heart-lung/lung transplant recipients (9.4 +/- 3.3 versus 15.3 +/- 0.9 ng/ml) (p < 0.01), and at latest follow-up significantly fewer heart transplant recipients were treated with maintenance corticosteroids (28% versus 75%; p < 0.01). In the heart-lung/lung group, no significant difference in tacrolimus levels was found between patients with and without diabetes, nor was there a significant difference in the average corticosteroid dose or number of pulses of corticosteroids per patient.

CONCLUSIONS

New-onset diabetes mellitus is rare in pediatric heart transplant recipients receiving tacrolimus-based immunosuppression, but it occurs with a high incidence after pediatric heart-lung/lung transplantation and usually develops during pulsed corticosteroid therapy. However, it is currently not possible to predict which heart-lung/ lung transplant recipients will have development of this serious complication.

Airway function tests and vocal cord paralysis in lung transplant recipients

Maximum expiratory and inspiratory flow-volume (MEFV, MIFV) curves, specific airway conductance (sGaw), and flexible fiberoptic laryngoscopy were examined in 8 pediatric lung transplant recipients with vocal cord paralysis (VCP). Six were heart-lung (H-L) and 2 double-lung (D-L) recipients, 7 had left VCP, and 1 had right VCP. Based on the pulmonary function tests (PFT), 2 subgroups could be distinguished in the 8 recipients with VCP. Group A (5/8 recipients; mean age, 13 +/- 3.4 years; mean height, 144.3 +/- 12.3 cm) had significantly reduced specific airway conductance (sGaw; < 2 SD from predicted) and normal MEF25, MEF50, peak expiratory flow (PEF), forced expiratory volume in 1 second (FEV1), and %FEV1/forced vital capacity (FVC); this pattern suggested variable extrathoracic airway obstruction. PIF was normal in 4/5 and reduced in 1/5 of these recipients. Group B (3/8 recipients with VCP; mean age, 17 +/- 2.4 years; mean height, 156.3 +/- 12.0 cm) had significantly reduced sGaw, MEF25, MEF50, PEF, FEV1, and %FEV1/FVC, implying primarily small airway obstruction. These recipients had bronchiolitis obliterans. The results suggest that a pattern of reduced sGaw and normal MEFs, PEF, FEV1, and PIF should raise the possibility of VCP in patients after lung transplantation. sGaw is more sensitive than PIF and PEF in identifying airway obstruction due to VCP, and should be routinely included in the follow-up evaluation of lung transplant recipients.

Effects of anaerobic exercise on the immune system in eight- to seventeen-year-old trained and untrained boys

OBJECTIVES

To determine the immunologic response to a brief bout of intense exercise in children and to determine the effects of prolonged activity and maturation level of the subjects on this response.

STUDY DESIGN

We determined counts of leukocytes and their subsets, counts of lymphocytes and their subsets, and natural killer (NK) cell activity and cell number before and 3 and 60 minutes after a Wingate anaerobic test (WAnT) in 16 male swimmers (9 to 17 years of age) and 17 male nonswimmers (9 to 17 years of age). Subjects were also categorized by pubertal status based on Tanner staging and by level of physical activity. The Student t test and analysis of variance were used to determine statistical significance, with values expressed as mean +/- SEM.

RESULTS

Three minutes after the WAnT, all children had increases in leukocytes (28%), lymphocytes (43%), and NK cells (395%) (p < 0.01). Swimmers had less baseline NK cell activity (54 +/- 6 cytolytic units) than nonswimmers (87 +/- 10 cytolytic units) after the WAnT (p < 0.01), although both groups showed an increase to similar levels of NK activity 3 minutes after exercise. Pubertal effects on these responses were not significant.

CONCLUSIONS

Our results demonstrate transient leukocytosis, lymphocytosis, and increases in NK cell number and activity in 8- to 17-year-old boys after a brief bout of intense exercise. Formal athletic training appears to be associated with a lower baseline NK cell activity, and yet such activity is still within the normal range for this age group. Further investigations are necessary to determine the impact of such training on overall health and the ability to fight infection.

Evolution of airway hyperresponsiveness in infants with severe congenital diaphragmatic hernia

Infants born with severe congenital diaphragmatic hernia (DH) characteristically have pulmonary hypoplasia. Airway hyperresponsiveness during the first 4 weeks of life can be demonstrated in most of these neonates. Early postnatal pulmonary development in infants with severe DH has not been well characterized. We examined lung growth in patients with congenital DH by using the forced deflation method to study pulmonary function in 18 infants on mechanical ventilation who survived neonatal repair of their congenital DH. Thirteen infants without primary pulmonary pathology who required general anesthesia for other surgery served as controls. Infants were further divided according to age at the time of testing into early (age < or = 7 days at time of testing) and late (age > or = 29 days) groups, yielding four groups of subjects: early diaphragmatic hernia (EDH): n = 9; mean age, 4.2 days; range, 1-7 days; early controls (EC): n = 8; mean age, 3.1 days; range, 1-6 days; late diaphragmatic hernia (LDH): n = 11; mean age, 57.7 days, range, 28-120 days; and late controls (LC); n = 5; mean age, 52.2 days; range 32-90 days. All infants were studied once, with the exception of two infants with DH who were studied on two occasions at EDH and LDH stages. A marked reduction in weight-corrected forced vital capacity (FVC) was seen in the EDH group (13.9 +/- 3.9 ml/kg) as compared to the EC group (44.4 +/- 4.9 ml/kg). During the ensuing 4 months of life, FVC in patients with LDH (24.5 +/- 1.9 ml/kg) was much higher than FVC in patients with EDH (P < 0.05). These findings demonstrate the presence of pulmonary hypoplasia in the EDH group and suggest subsequent rapid postnatal lung growth. An index of rate constant, MEF25/FVC, as compared with control groups was abnormally elevated in EDH subjects (1.87 +/- 0.30/second vs 1.16 +/- 0.32/ second, P < 0.05), indicating significantly increased lower airway caliber relative to lung volume. The severe reduction of the rate constant in the LDH group (0.36 +/- 0.05/second vs 0.73 +/- 0.07/second, P < 0.05) suggests the development of lower airway obstruction. After the administration of a nebulized bronchodilator (BD), an increase in MEF25 (32.9%) in the EDH group was not significant, but an increase of 134.7% in the LDH group was significant (P < 0.05). Although the study utilized a cross-sectional design with most of the infants in either the early or late group, present findings suggest that infants with EDH have lung restriction reflecting pulmonary hypoplasia. These infants developed lower airway obstruction and airway hyperresponsiveness with only mild fixed obstruction over the first 4 months of life.

Pediatric lung transplantation: indications and contraindications

As the practice of lung transplantation in children evolves, the indications are expanding. The major diagnostic groups for which transplantation is offered are similar to those used in adult lung transplantation with the notable absence of obstructive lung disease. Of all children under the age of 18 years undergoing lung transplantation, cystic fibrosis accounts for approximately 35%, pulmonary vascular disease, with or without associated congenital heart disease, accounts for 25-30%, and interstitial lung diseases comprise about 10%. The other categories included retransplantation and a variety of diagnoses which by themselves describe an unusual form of end-stage pulmonary disease. The selection of candidates with transplantable diagnoses is crucial, and as this specialty evolves the contraindications have as well. Colonization of the airway with resistant bacterial or fungal organisms, history of multiple prior thoracic procedures, need for mechanical ventilation, diabetes mellitus, and the presence of other organ failure constitute some relative contraindications for transplantation. Retransplantation is a controversial issue that has not yet been resolved.

Interferon-alpha affects the immune response in post-transplant lymphoproliferative disorder

Post-transplant lymphoproliferative disorder (PTLD) is associated with Epstein-Barr virus (EBV) and characterized by fever, lymphadenopathy, and graft dysfunction. We describe the clinical course of an EBV seronegative 11-yr-old boy who underwent double lung transplantation and subsequently developed PTLD in the graft. A reduction in immunosuppression and the addition of acyclovir did not result in improvement. Treatment with interferon-alpha (IFN-alpha), however, led to dramatic clinical, radiographic, and histologic improvement. Semiquantitative measurements of cytokine mRNA in his bronchoalveolar lavage cells prior to therapy with IFN-alpha revealed high levels of IL-4 and IL-10 mRNA, which decreased significantly with treatment. We speculate that the beneficial effect of IFN-alpha in the treatment of PTLD is directly related to the inhibition of type 2 helper (Th2-like) T-cells.

Nutrition in the pediatric double lung transplant patient with cystic fibrosis

Cystic fibrosis (CF) is the most common lethal genetic disease in the white population. The pulmonary infections and pancreatic insufficiency make CF a medically challenging disease. Although the importance of nutrition in the CF patient is known, approximately 50% of CF patients are in less than the 10th percentile for weight and height as reported by the 1991 CF Foundation Registry of 114 CF Centers in the United States. This paper addresses the nutritional status of 10 pediatric CF patients who underwent double lung transplant at Children's Hospital of Pittsburgh between August 1991 and May 1993. Patients who survived beyond 1 year gained a significant amount of weight sooner after transplant than those who survived less than 1 year. Gastrostomy tube feedings were more effective than oral intake for weight gain after transplant. CF patients with pancreatic insufficiency have more difficulty with adjustment of doses of immunosuppressive agents for reasons that are not clearly understood.

Critical issues in pediatric lung transplantation

Forty children (aged 1 to 18 years, 27 female and 13 male) have undergone heart-lung (21), double lung (17), and single lung (2) transplant procedures at our center from 1985 through April 1994. The indications for transplantation have been diverse, primary pulmonary hypertension (10), cystic fibrosis (11), congenital heart disease (10), arteriovenous malformation (3), emphysema (1), graft-versus-host disease (1), rheumatoid lung (1), cardiomyopathy (1), desquamative interstitial pneumonitis (1), and Proteus syndrome (1). The actuarial 1-year survival was 73% (mean follow-up 2 years). One-year actuarial survival for disease groups ranged from 60% for cystic fibrosis to 90% for congenital heart disease. We have identified six issues critical to the patient and programatic survival of pediatric lung transplantation. Our experience and management strategies in these areas are reviewed. Cytomegalovirus: Cytomegalovirus disease developed in six of eight patients with cytomegalovirus mismatching (donor +/recipient-) and in seven of 32 patients who survived more than 30 days (23%). All but cytomegalovirus donor -/recipient- patients were treated with ganciclovir for 4 weeks after transplantation. Obliterative bronchiolitis: Obliterative bronchiolitis developed in seven of 32 (25%) patients who survived more than 30 days. Obliterative bronchiolitis was manifest within the first posttransplantation year as a rapid decline in small airway function. Aggressive augmentation of immunosuppression has been used with little success. Posttransplantation lymphoproliferative disease: Posttransplantation lymphoproliferative disease developed in five of 32 (15%) patients who survived more than 30 days developed. One patient died (17% mortality) despite retransplantation. In four patients the disease resolved with reduction in immunosuppression alone, and one required the addition of interferon alfa. Cystic fibrosis: We have changed our management strategies to avoid triple drug immunosuppression, perioperative blood and bronchial cultures, aggressive antimicrobial therapy, and exclusion of patients with panresistant organisms; this has resulted in elimination of infectious mortalities thus far in the pediatric cystic fibrosis group. Airways: In 21 heart-lung recipients with tracheal anastomoses we have had no airway complications. The double and single lung transplant recipients accounted for 34 bronchial and one tracheal anastomoses. Three (9%) bronchial stenoses developed. Two were treated with silicone stents and one with balloon dilation.(ABSTRACT TRUNCATED AT 400 WORDS)

Hypertrophic osteoarthropathy in a child with follicular bronchiolitis

Hypertrophic osteoarthropathy (HOA) is a syndrome affecting the bones, soft tissue, and joints, often occurring in association with chronic pulmonary disorders. Radiography has traditionally been the imaging modality employed to confirm this diagnosis. However, radionuclide bone imaging provides a sensitive method for the detection of HOA and correlates well with the clinical manifestations. The authors's describe the case of a child with HOA in association with follicular bronchiolitis, a rare chronic pulmonary disorder, whose HOA was diagnosed by radionuclide imaging.

Pseudomonas cepacia empyema necessitatis after lung transplantation in two patients with cystic fibrosis

Lung transplantation is an accepted modality for patients with cystic fibrosis (CF) who have end-stage respiratory failure. The postoperative course of these patients is often complicated by serious infections with organisms such as Pseudomonas aeruginosa and Pseudomonas cepacia that may be multiply resistant to conventional antimicrobial agents. We describe two patients with CF who, after double lung transplantation, developed the unusual complication of empyema and empyema necessitatis due to P cepacia that was resistant to all tested antibiotics.

Complications of pediatric lung and heart-lung transplantation

As more children receive lung and heart-lung transplants, understanding posttransplantation complications becomes more important. Complications can be categorized as 1) anatomic and surgical, 2) infectious, 3) rejection, 4) posttransplantation lymphoproliferative disease (PTLD), and 5) drug-related. In the early posttransplantation period, reimplantation injury and vascular obstruction with thrombus formation may occur, whereas stenosis at tracheal or bronchial anastomotic sites develops more slowly. Infections in the transplanted lung are common, and can be caused by bacteria, viruses, fungi, or protozoans. Both acute and chronic rejection are potentially serious. Frequent or severe episodes of acute rejection increase the risk of chronic rejection, characterized by obliterative bronchiolitis. Differentiating rejection from infection requires tissue, obtained through transbronchial or open lung biopsy. PTLD, related to Epstein-Barr virus infection, is common in children, and difficult to treat. Finally, drug toxicity from immunosuppressive agents causes considerable morbidity. Increased understanding will continue to improve the outcome for children undergoing lung and heart-lung transplantation.

Acute myocardial infarction in a young boy with nephrotic syndrome: a case report and review of the literature

A 7-year-old boy with a 5-year history of steroid-unresponsive nephrotic syndrome due to minimal change disease presented with acute myocardial infarction. Angiography was suggestive of a dissected atherosclerotic plaque at the initial and mid portions of the right coronary artery, as well as a lesion in the mid portion of the circumflex artery. The child had a long history of extreme hypercholesterolemia and hypertriglyceridemia, along with apolipoprotein-E 4/3 phenotype. The mother, who also has apolipoprotein-E 4/3 phenotype, has mild hypercholesterolemia. The case suggests that children with long-lasting nephrotic syndrome and even mild familial propensity for hyperlipidemia may be at increased risk for ischemic cardiovascular events. The literature is reviewed regarding the relationship between nephrotic syndrome and the incidence of ischemic heart disease.

Ear disease in children with cystic fibrosis

OBJECTIVE

To assess otitis media in children with cystic fibrosis.

DESIGN

Prospective prevalence survey.

SETTING

Otolaryngology and cystic fibrosis/pulmonology outpatient clinics, Children's Hospital of Pittsburgh (Pa), a regional referral center.

PATIENTS

Seventy patients, aged 4 months to 17 years, with documented cystic fibrosis who presented to the cystic fibrosis/pulmonary clinic with scheduled appointments were asked to volunteer for the study. The 70 patients recruited represent approximately one fourth of the children younger than 17 years with cystic fibrosis who were followed up by the cystic fibrosis/pulmonary clinic.

INTERVENTION

Ear, nose, and throat examination including pneumatic otoscopy, with tympanometry when indicated; relevant history taking.

MAIN OUTCOME MEASURE

Presence or absence of otitis media.

RESULTS

Seven (10%) of the 70 patients had unilateral or bilateral otitis media.

CONCLUSIONS

Children with cystic fibrosis have a low prevalence of otitis media compared with normal children.

Pediatric lung transplantation for graft-versus-host disease following bone marrow transplantation

Nine years after receiving a bone marrow transplant for aplastic anemia, a 14-year-old girl with severe pulmonary disease associated with graft-versus-host disease received a double lung transplant. Subsequent to lung transplant, her lung function improved dramatically (FEV1 increasing from 20 to 73 percent predicted normal, residual volume decreasing from 316 to 130 percent predicted normal values). The patient is currently well 15 months after transplant, while receiving immunosuppression consisting of FK506 and azathioprine. Double lung transplantation may offer a therapeutic option for the treatment of graft-versus-host pulmonary disease in selected patients.

Experience with pediatric lung transplantation

Heart-lung transplantation and lung transplantation have become accepted techniques in adult patients with end-stage cardiopulmonary disease. We report here our experience between July 1985 and March 1993 with 34 children (< 20 years) who underwent heart-lung (n = 18) or lung transplantation (n = 17). Indications for transplantation included cystic fibrosis (n = 9), congenital heart disease with Eisenmenger complex (n = 9), primary pulmonary hypertension (n = 8), pulmonary arteriovenous malformations (n = 2), desquamative interstitial pneumonia (n = 2), Proteus syndrome with multicystic pulmonary disease (n = 1), graft-versus-host disease (n = 1), rheumatoid lung disease (n = 1), and bronchiolitis obliterans and emphysema (n = 1). Twenty-six patients (76%) have survived from 1 to 88 months after transplantation; most patients have returned to an active lifestyle. Of the eight deaths, four were due to infections, two to multiorgan failure, 1 to posttransplant lymphoproliferative disease, and one to donor organ failure. Four of the patients who died had cystic fibrosis. Despite considerable morbidity related to infection, rejection, and function of the heart-lung and lung allograft in some patients, our results with this potentially lifesaving procedure in the pediatric population have been encouraging.

Cardiopulmonary bypass significantly reduces surfactant activity in children

Lung injury remains an important problem after cardiopulmonary bypass. The contribution of altered surfactant concentration or activity to pulmonary dysfunction after cardiopulmonary bypass is unclear. Recent evidence indicates that alveolar surfactant exists in specific aggregate forms that differ with respect to density, phospholipid composition, and function. A transition from surface active, higher density, large aggregates of surfactant to lower density, small aggregates that possess reduced surface activity has been demonstrated after experimental lung injury. The purpose of the present study was to examine surfactant aggregate fractions before and after bypass in children. Twelve acyanotic patients, aged 2 to 12 years, underwent intraoperative pulmonary function testing followed by bronchoalveolar lavage before incision and approximately 1 hour after termination of cardiopulmonary bypass. Saturated phosphatidylcholine pool sizes and total protein content of the small- and large-aggregate fractions of bronchoalveolar lavage fluid were determined. One hour after termination of cardiopulmonary bypass, the ratio of saturated phosphatidylcholine in small-aggregate as compared with that in large-aggregate fractions increased (mean +/- standard error) from 0.19 +/- 0.03 to 0.37 +/- 0.07 (p < 0.02), as did the ratio of saturated phosphatidylcholine to protein in the small-aggregate fraction (from 0.04 +/- 0.01 to 0.08 +/- 0.02, p < 0.05). Reductions in forced vital capacity (-19% +/- 5%), inspiratory capacity (-15% +/- 3%), and small airway flow rates (-32% +/- 6%) were also observed after bypass. These changes were accompanied by a fivefold increase in alveolar polymorphonuclear leukocyte content. The present study suggests that cardiopulmonary bypass of moderate duration in relatively healthy children is associated with surfactant changes that are similar in type and magnitude to those observed in experimental lung injury.

Pediatric lung transplantation: expanding indications, 1985 to 1993

The application of lung transplantation to the pediatric population was a natural extension of the success realized in our adult transplant program, which began in 1982. Thirty-two pediatric patients (age range 1 to 18 years) have undergone heart-lung (n = 16), double-lung (n = 14), and single-lung (n = 2) transplantation procedures. The cause of end-stage lung disease was primary pulmonary hypertension (n = 7), congenital heart disease (n = 7), cystic fibrosis (n = 9), pulmonary arteriovenous malformation (n = 2), desquamative interstitial pneumonitis (n = 2), graft-versus-host disease (n = 1), emphysema (n = 1), rheumatoid lung (n = 1), cardiomyopathy (n = 1), and Proteus syndrome (n = 1). Six patients (19%) underwent pretransplantation thoracic surgical procedures. The survival rate was 78% at a mean follow-up of 1.8 years. The survival rate in the 23 recipients without cystic fibrosis was 87% (95% since 1985). The actuarial 1-year survival rate in the nine recipients with cystic fibrosis was 55%. Immunosuppression was cyclosporine (n = 9) or FK 506 (n = 23)-based therapy with azathioprine and steroids. Children were followed up by spirometry, transbronchial biopsy, and primed lymphocyte testing of bronchoalveolar lavage fluid. The mean number of treated episodes of rejection per patient in the groups treated with cyclosporine and FK 506, respectively, was 1.0 and 1.2 at 30 days, 0.67 and 0.38 at 30 to 90 days, and 2.33 and 0.46 at greater than 90 days (p < 0.001, Fisher exact test).(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchoalveolar lavage and transbronchial biopsy in children following heart-lung and lung transplantation

Between July 1985 and March 1992, 20 children received either heart-lung (11), double lung (8), or single lung (1) transplants at our center. Since 1988, flexible fiberoptic bronchoscopy with bronchoalveolar lavage and transbronchial biopsy have been carried out to monitor for rejection or infection in these patients. As of March 31, 1992, we have performed a total of 112 transbronchial biopsies in our patients, who ranged from 6.8 to 18 years of age and 19.3 to 67.3 kg in weight. All but two of these procedures were carried out using conscious sedation and a transnasal approach. Four to seven biopsy samples were obtained at each procedure. One patient had hemorrhage (< 100 ml) and no patient had pneumothorax as a complication. Of the biopsy samples, 72.4 percent had a surface area of greater than 2 mm2, and 89.5 percent of the biopsy samples were deemed adequate for pathologic interpretation. We believe that for the majority of pediatric lung or heart-lung recipients, flexible bronchoscopy and transbronchial biopsy using conscious sedation and a transnasal approach is safe and permits the recovery of adequate tissue for pathologic evaluation. The avoidance of general anesthesia, endotracheal intubation, and mechanical ventilation at the time of bronchoscopy and transbronchial biopsy probably decreases the likelihood of pneumothorax as a complication of the procedure.

Chronic Pseudomonas aeruginosa endobronchitis in rhesus monkeys: II. A histopathologic analysis

We have recently established a rhesus monkey model of chronic Pseudomonas aeruginosa (PA) endobronchitis by bronchoscopic instillation of PA-embedded agar beads. All experimental animals developed chronic neutrophilic endobronchitis similar to chronic PA endobronchitis in cystic fibrosis (CF). Histopathologic studies further confirmed similarities to chronic PA endobronchitis in CF, including marked peribronchial inflammation, epithelial damage, presence of degraded cilia and ciliary abnormalities, appearance of PA bacterial clusters, mucosal hyperplasia, goblet cell hypertrophy/hypersecretion, airway obstruction, alveolar abnormalities, bronchiectasis, and fibrosis.

Nonbronchoscopic bronchoalveolar lavage in mechanically ventilated infants: technique, efficacy, and applications

Bronchoalveolar lavage with the fiberoptic bronchoscope is commonly used for the diagnosis of pulmonary infections in mechanically ventilated adults and children. However, its use for intubated infants is precluded because the small artificial airway does not permit the passage of the bronchoscope. We have developed a technique for nonbronchoscopic bronchoalveolar lavage, performed via a sterile, disposable feeding tube. We have used this technique in 15 infants with diffuse interstitial disease and/or atelectasis, while they were intubated and mechanically ventilated. The volume of the lavage effluent averaged 70.3% of the volume instilled. Specific diagnosis on the basis of the cytologic evaluation and/or culture of the lavage fluid was possible in 9 (60%) patients. Two patients with atelectasis showed radiographic evidence of improvement following the procedure. There were no complications. We conclude that nonbronchoscopic bronchoalveolar lavage is well tolerated, and clinically useful in small, mechanically ventilated infants with respiratory failure due to diffuse pulmonary disease. This technique provides a lower risk alternative to more invasive, and costly procedures.

Pediatric lung transplantation. The years 1985 to 1992 and the clinical trial of FK 506

The application of lung transplantation to the pediatric population was a natural extension of the success realized in our adult transplantation program, which began in 1982. Twenty pediatric patients (age range 3 to 18 years) have had heart-lung (n = 11), double lung (n = 8), and single lung (n = 1) transplantation procedures. The causes of end-stage lung disease were primary pulmonary hypertension (n = 7), congenital heart disease (n = 5), cystic fibrosis (n = 4), pulmonary arteriovenous malformation (n = 2), graft-versus-host disease (n = 1), and desquamative interstitial pneumonitis (n = 1). Four (20%) patients had thoracic surgical procedures before the transplantation operation. The survival was 80% at a mean follow-up of 2 years. Immunosuppressive drugs included cyclosporine (n = 9) or FK 506 (n = 11) based therapy with azathioprine and steroids. Children were followed up by means of spirometry, transbronchial biopsy, and primed lymphocyte testing of bronchoalveolar lavage fluid. The mean number of treated episodes of rejection was 1.4 at 30 days, 0.5 at 30 to 90 days, and 1.4 at more than 90 days, and the first treated rejection episode occurred on average 28 days after the operation. Obliterative bronchiolitis developed in four (25%) of 16 patients surviving more than 100 days. Results of pulmonary function tests have remained good in almost all recipients. The greatest infectious risk was that of cytomegalovirus: one death and one case of pneumonia. Posttransplantation lymphoproliferative disease was diagnosed in two (12.5%) patients; both recovered. The most common complications were hypertension (25%) and postoperative bleeding (15%). Early results indicate that lung transplantation is a most promising therapy for children with severe vascular and parenchymal lung disease.

Diabetic ketoacidosis in cystic fibrosis

OBJECTIVE

To differentiate the insulin-dependent glucose intolerance associated with cystic fibrosis from type I diabetes mellitus in patients with cystic fibrosis.

DESIGN

Patient report.

SETTING

Tertiary care referral center.

PARTICIPANT

An 11-year-old boy with cystic fibrosis who developed diabetic ketoacidosis. MEASUREMENT/MAIN RESULT: Biochemical, immunologic, and molecular techniques were used to support the sporadic association of type I diabetes mellitus in a patient with cystic fibrosis. Cystic fibrosis was confirmed by sweat test and further supported by the demonstration of a heterozygous deletion of the F508 locus. Evidence for the diagnosis of type I diabetes mellitus was developed from the clinical presentation of diabetic ketoacidosis with hyperglycemia, ketonemia, and ketonuria. Immunologic evidence included the demonstration of anti-insulin antibodies. The demonstration of homozygous absence of aspartic acid at position 57 of the HLA DQ-beta chain placed this child at high risk of type I diabetes mellitus.

CONCLUSION

The clinical presentation and the presence of immunologic and genetic markers characteristic of type I diabetes mellitus supports the concordance of cystic fibrosis and type I diabetes mellitus in this patient.

Fatal pulmonary aspergillosis presenting as acute eosinophilic pneumonia in a previously healthy child

A previously healthy boy presented with cough and diffuse pulmonary interstitial infiltrates. Acute eosinophilic pneumonia was diagnosed by bronchoalveolar lavage in the absence of a demonstrable infectious etiologic agent. Corticosteroid therapy resulted in immediate improvement but was followed by respiratory distress and death from invasive aspergillosis and Pseudomonas cepacia sepsis.

The deficient migration in vitro of lung macrophages from newborn rats normalizes after three days of maturation in situ

Because there are functional deficiencies in neonatal phagocytes, we investigated age-dependent differences in the directed migration of rat pulmonary macrophages (PM). Directed migration of PMs from newborn (less than 24 h old) rats towards partially purified rat C5a was lower than that of PMs from adults, but reached adult levels by the third post-natal day. Calculation of the dose of C5a resulting in a half-maximal migratory response (ED-50) revealed that the ED-50s for all age groups studied were similar. These results suggest that responding PMs at all times after birth have comparable sensitivity to C5a, but that a lower percentage of newborn PMs migrate toward this factor because of defects in either signal transduction or cell motility.

Expression of mucin synthesis and secretion in human tracheobronchial epithelial cells grown in culture

The effects of culture conditions on growth and differentiation of human tracheobronchial epithelial (HTBE) cells have been defined. Epithelial cells were dissociated from tissues by protease treatment and were plated on tissue culture dishes in F12 medium supplemented with insulin, transferrin, epidermal growth factor, hydrocortisone, cholera toxin, bovine hypothalamus extract, and retinol. HTBE cells did not express any mucociliary function (ciliogenesis or mucin secretion) on tissue culture plastic, but they could be passaged 3 to 5 times with a total of 10 to 25 population doublings. Cells from early passages re-express both these functions when transplanted to tracheal grafts. When tissue culture plates were coated with collagen film or collagen gel substrata, cell attachment and proliferation were stimulated. However, the expression of mucous cell function in culture occurred only when cells were plated on collagen gel substrata and vitamin A (retinol) was present in the medium. Mucous cell differentiation under optimal conditions was defined by ultrastructural studies, by immunologic studies with mucin-specific monoclonal antibodies, and by carbohydrate and amino acid compositional analyses of mucin-like glycoproteins purified from culture medium. These results demonstrate for the first time that HTBE cells can express mucin synthesis and secretion under appropriate culture conditions.

Prediction of intravenous theophylline dosage based on a single, nonsteady-state concentration: a clinical study of childhood status asthmaticus

A pharmacokinetic model was applied to achieve therapeutic serum theophylline concentrations rapidly in 25 children with status asthmaticus. A sustained release theophylline preparation had been taken within 36 hours by 12 children; within 14 hours, seven had taken an immediate release preparation; for six children, no theophylline was taken before hospital admission. Single serum theophylline concentrations were determined at nonsteady-state conditions within 13.5 hours of admission (median 6.75 hours). An iterative program was applied to predict the steady-state theophylline concentration as well as necessary adjustments in dosage. Measured steady-state concentrations were then compared with the predicted values. The median measured steady-state concentration was 15 mg/L, and the median predicted steady-state level was 13 mg/L. The least squares regression line was: Measured = 0.738 predicted + 4.77; r = .721, P less than .01. No patient experienced symptoms of toxicity. This technique affords the possibility of accurate prediction of steady-state theophylline concentrations and dosing requirements with a minimum number of serum concentration determinations in children with status asthmaticus.

Adipose tissue abnormalities in cystic fibrosis: noninvasive determination of mono- and polyunsaturated fatty acids by carbon-13 topical magnetic resonance spectroscopy

Natural abundance in vivo carbon-13 topical magnetic resonance (TMR) spectroscopy was used to assess human adipose tissue stores of essential (polyunsaturated) fatty acids. TMR spectra were obtained from 17 normal volunteers and nine cystic fibrosis patients using an Oxford TMR-32 with a surface coil that sampled tissue less than 1 cm below the surface of an extremity. Spectra were taken of lower leg adipose tissue. Polyunsaturated fatty acid content was determined by comparing peak heights of the polyunsaturated peak (internal unsaturated carbons, 128 ppm) to C-1 carboxyl groups (173 ppm). Monounsaturated fatty acid content was determined by subtracting the polyunsaturated peak from the peak observed for all unsaturated carbons (external unsaturated carbon, 130 ppm) and dividing this ratio by the carboxyl peak. In vivo TMR of normal volunteers resulted in observed polyunsaturated fatty acid content of 17.8 +/- 2.1% and a monounsaturated content of 44.8 +/- 3.8%. The polyunsaturated and monounsaturated fatty acid content of adipose tissue from the cystic fibrosis patients was 15.0 +/- 2.0% (p less than 0.005 versus normal volunteers) and 47.8 +/- 6.5% (NS), respectively. One cystic fibrosis patient without fat malabsorption had decreased adipose polyunsaturates, whereas another patient on high calorie gastrostomy feeds had normal levels. Carbon-13 TMR spectroscopy is a sensitive, noninvasive technique for determining essential fatty acid status in subcutaneous adipose tissue of patients with cystic fibrosis.

The ontogeny of pulmonary defenses: alveolar macrophage function in neonatal and juvenile rhesus monkeys

Using the technique of bronchoalveolar lavage, we isolated alveolar macrophages (AM) from the lower respiratory tract of newborn (1-4 days of age), infant (6-10 days of age), juvenile (3-6 months of age), and adult rhesus monkeys. The AM thus obtained were assayed in vitro to determine their chemotactic, phagocytic, and candidicidal capabilities. The predominant (greater than or equal to 89%) cell type in bronchoalveolar lavage effluent in all ages was the AM. Chemotaxis, phagocytosis, and killing of Candida albicans were markedly impaired in neonatal AM as compared with those from infants, juveniles, and adults. AM chemotactic activity achieved normal adult values by 6 days of age. Phagocytosis, and to a lesser extent candidicidal activity, were significantly improved in 6-day-old animals, but adult levels were still not achieved even by 6 months of age.

Antidiuretic hormone excess in infant botulism

Two infants developed evidence of antidiuretic hormone excess as a complication of infant botulism. Neither child received mechanical ventilatory support before the development of hyponatremia, serum hyposmolality, and urinary hyperosmolality. Both infants responded to fluid-intake restriction. The appearance of hyponatremia in an infant with botulism should suggest antidiuretic hormone excess. The recognition of this entity will lead to its appropriate management with fluid-intake restriction.

Orthotopic liver transplantation in patients with cystic fibrosis

An 11-year-old boy who had cystic fibrosis underwent an orthotopic liver transplantation. His immediate postoperative course was not unusually complicated when compared with other liver transplant recipients. Transplantation did not correct abnormalities in the sweat test or the respiratory disease. Cholestasis due to obstruction of the recipient duct with tenacious bile was cleared by instilling N-acetylcysteine into the duct. On the 48th day after the transplantation, he died of an intraventricular and intracerebral hemorrhage caused by an Aspergillus brain abscess. We conclude that certain patients with cystic fibrosis may be appropriate candidates for liver transplantation, but their pre- and post-operative management may need to differ from other liver transplant recipients.

Polymicrobial bacterial sepsis and defective neutrophil chemotaxis in an infant with cystic fibrosis

A 4 1/2-month-old, white girl was admitted to the hospital with respiratory distress and persistent polymicrobial bacteremia. Cystic fibrosis associated with malnutrition and a transient defect in peripheral neutrophil chemotaxis was diagnosed. This remarkable combination of presenting features in a patient with cystic fibrosis is the focus of this case report.

Severe kyphoscoliosis, breathing, and sleep: the "Quasimodo" syndrome during sleep

Five adult subjects with severe kyphoscoliosis were monitored during sleep. Several types of breathing abnormalities, including obstructive apnea and hypopnea, were noted. The lowest oxygen desaturations occurred during rapid eye movement (REM) sleep. Arterial pressure, continuously measured in one subject, progressively increased throughout the night in association with abnormal breathing. The use of a cuirass ventilator did not improve the nocturnal problem.

Circulating platelet products in unstable angina pectoris

In 19 patients with unstable angina pectoris at rest, plasma levels of the platelet-derived proteins beta-thromboglobulin and platelet factor 4 were significantly elevated in blood samples obtained during or within 4 hours after episodes of angina, but were usually normal during quiescent intervals. Plasma levels of the arachidonic acid metabolite thromboxane B2 were less clearly related to angina, and there was no association of angina with levels of the coagulation product fibrinopeptide A. This demonstration of an association of platelet activation and secretion with unstable angina pectoris by radioimmunoassay of circulating platelet constituents offers a new approach to assessment of therapy in ischemic heart disease and suggests that agents that alter platelet function should be evaluated in patients with unstable angina.

Fatal myocardial toxicity during continuous infusion intravenous isoproterenol therapy of asthma

We recently utilized continuous infusion intravenous isoproterenol in the treatment of respiratory failure in an 18-yr-old steroid-dependent asthmatic female. Aminophylline, hydrocortisone, aerosolized isoetharine, and oxygen were also administrered. The patient responded to this therapy, with PaCO2 falling from 70 torr to 33 torr in 18 hr. The maximum isoproterenol dosage administered was 0.32 microgram/kg/min. Thirty-six hours following the institution of therapy, while the isoproterenol was being tapered, the patient experienced an increase in respiratory distress followed by cardiac arrest. Postmortem examination revealed multiple small areas of myocardial necrosis. These findings, unusual in asthma, probably were related to the effects of isoproterenol or the combination of isoproterenol and aminophylline on the stressed myocardium. The vulnerability of the hypoxic myocardium to the effects of isoproterenol suggests that careful cardiac monitoring is essential in the management of patients receiving this medication for treatment of respiratory failure secondary to severe asthma.