Features and Outcomes of Methamphetamine-associated Pulmonary Arterial Hypertension

RATIONALE

Although amphetamines are recognized as "likely" agents to cause drug- and toxin-associated pulmonary arterial hypertension (PAH), (meth)amphetamine-associated PAH (Meth-APAH) has not been well described.

OBJECTIVES

To prospectively characterize the clinical presentation, histopathology, and outcomes of Meth-APAH compared with those of idiopathic PAH (iPAH).

METHODS

We performed a prospective cohort study of patients with Meth-APAH and iPAH presenting to the Stanford University Pulmonary Hypertension Program between 2003 and 2015. Clinical, pulmonary angiography, histopathology, and outcomes data were compared. We used data from the Healthcare Cost and Utilization Project to estimate the epidemiology of PAH in (meth)amphetamine users hospitalized in California.

MEASUREMENTS AND MAIN RESULTS

The study sample included 90 patients with Meth-APAH and 97 patients with iPAH. Patients with Meth-APAH were less likely to be female, but similar in age, body mass index, and 6-minute-walk distance to patients with iPAH. Patients with Meth-APAH reported more advanced heart failure symptoms, had significantly higher right atrial pressure (12.7 ± 6.8 vs. 9.8 ± 5.1 mm Hg; P = 0.001), and had lower stroke volume index (22.2 ± 7.1 vs. 25.5 ± 8.7 ml/m²; P = 0.01). Event-free survival in Meth-APAH was 64.2%, 47.2%, and 25% at 2.5, 5, and 10 years, respectively, representing more than double the risk of clinical worsening or death compared with iPAH (hazard ratio, 2.04; 95% confidence interval, 1.28-3.25; P = 0.003) independent of confounders. California data demonstrated a 2.6-fold increase in risk of PAH diagnosis in hospitalized (meth)amphetamine users.

CONCLUSIONS

Meth-APAH is a severe and progressive form of PAH with poor outcomes. Future studies should focus on mechanisms of disease and potential therapeutic considerations.

Pathology of radiation and anthracycline cardiotoxicity

Radiation-induced heart disease (RIHD) and anthracycline cardiotoxicity are two patterns of cardiac dysfunction caused by therapeutic interventions to treat malignancies. They occur in both the pediatric and adult populations and there is evidence to suggest that pediatric patients are at greater risk. This is due in part to the longer survival rates but also reflects increased susceptibility to the attendant complications caused by both therapies. Radiation can cause injury to all the components of the heart, including the vasculature, while anthracycline toxicity is generally limited to the myocardium.

A DNA microarray survey of gene expression in normal human tissues

A systematic survey of gene expression in 115 human tissue samples using cDNA microarrays provides a dataset that can be used as a baseline for comparison with expression in diseased tissue.

Background

Numerous studies have used DNA microarrays to survey gene expression in cancer and other disease states. Comparatively little is known about the genes expressed across the gamut of normal human tissues. Systematic studies of global gene-expression patterns, by linking variation in the expression of specific genes to phenotypic variation in the cells or tissues in which they are expressed, provide clues to the molecular organization of diverse cells and to the potential roles of the genes.

Results

Here we describe a systematic survey of gene expression in 115 human tissue samples representing 35 different tissue types, using cDNA microarrays representing approximately 26,000 different human genes. Unsupervised hierarchical cluster analysis of the gene-expression patterns in these tissues identified clusters of genes with related biological functions and grouped the tissue specimens in a pattern that reflected their anatomic locations, cellular compositions or physiologic functions. In unsupervised and supervised analyses, tissue-specific patterns of gene expression were readily discernable. By comparative hybridization to normal genomic DNA, we were also able to estimate transcript abundances for expressed genes.

Conclusions

Our dataset provides a baseline for comparison to diseased tissues, and will aid in the identification of tissue-specific functions. In addition, our analysis identifies potential molecular markers for detection of injury to specific organs and tissues, and provides a foundation for selection of potential targets for selective anticancer therapy.

Pulmonary glial heterotopia in a monoamniotic twin

Brain heterotopia in the lungs is rare, but when it occurs in an otherwise healthy newborn, it presents a difficult diagnostic problem and uncertain pathophysiology. We report on a 2-week-old premature infant who presented with respiratory distress and widespread cystic lung changes identified by chest imaging studies. Autopsy demonstrated that the cyst walls were composed of well-differentiated neuroglial tissue, which was confirmed by immunohistochemistry. The cysts were partially lined by bronchial epithelium and contained keratinous debris. For the first time, we demonstrate that the debris stain for human chorionic gonadotropin, compatible with aspirated amnion. There were no other congenital abnormalities. Her monoamniotic twin was anencephalic and died at birth. Although the etiology of glial heterotopia in the lungs is unknown, the majority of cases are associated with anencephalic newborns. Some authors postulated that this heterotopia may therefore be a consequence of fetal aspiration of brain tissue. Other possibilities include glial predominant teratomas, hamartomatous malformations, and abnormal neural crest migration. Our review of the 21 cases reported over the past century suggests that in utero aspiration of glial cells, or abnormal neural crest migration, are the most likely explanations for this rare and fatal disease.

Sudden death in an 8-week-old infant with Beckwith-Wiedemann syndrome

The authors report a case of a 2-month-old girl diagnosed with Beckwith-Wiedemann syndrome (BWS) who was born prematurely and died suddenly in the hospital just before being discharged. BWS is a malformation syndrome associated with an increased risk of childhood tumors. The major features of BWS are macroglossia, abdominal wall defects, and visceromegaly, frequently leading to premature birth. Due to complex inheritance patterns, a predominance of nonfamilial cases, and the variability in expression of the features (termed incomplete penetrance), the risk of delayed diagnosis is evident. Secondary to hyperplastic pancreatic islands, hypoglycemia occurs frequently, and if not anticipated, adequate measures for prevention of hypoglycemic episodes may be delayed, resulting in possible intellectual deficits. The infant presented here died of natural causes: immaturity of the lungs resulting in marginal respiratory function and compounded by increased risk for asphyxia secondary to the enlarged tongue. The clinical history and findings in this infant are discussed in respect to the genetic syndrome with their relevance to medicolegal examination and the causes and manner of death.