Overview
Secondary pulmonary alveolar proteinosis (secondary PAP) is a rare lung disease where a fatty, protein-rich substance called surfactant builds up inside the tiny air sacs of the lungs (called alveoli). This buildup makes it very hard for oxygen to pass from the lungs into the bloodstream. Unlike the primary form of this disease, secondary PAP is caused by another underlying condition — most often a blood disorder, a weakened immune system, certain infections, or exposure to toxic dusts or chemicals. Common underlying causes include leukemia, lymphoma, myelodysplastic syndrome, HIV infection, and exposure to silica dust or other inhaled particles. The main symptoms are a gradual worsening shortness of breath, a dry cough, and fatigue. Some people also develop low oxygen levels in the blood, which can cause bluish lips or fingertips. The disease can range from mild to life-threatening depending on how severe the buildup is and how well the underlying cause can be treated. Treatment focuses on managing the root cause whenever possible. When the lung buildup becomes severe, a procedure called whole lung lavage (washing out the lungs with saline fluid) can provide significant relief. Newer therapies targeting the immune system are also being explored. Early diagnosis and treatment of the underlying condition are key to improving outcomes.
Also known as:
Key symptoms:
Shortness of breath, especially with activityDry cough that does not go awayUnusual tiredness or fatigueLow oxygen levels in the bloodBluish tint to lips or fingertips (cyanosis)Chest tightness or discomfortUnintended weight lossFever (especially if infection is also present)Difficulty exercising or doing everyday tasksCrackling sounds in the lungs heard by a doctor
Sporadic
Usually appears on its own, not inherited from a parent
Variable
Can begin at different ages, from infancy through adulthood
FDA & Trial Timeline
2 eventsUniversity of Wisconsin, Madison — PHASE2
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Secondary pulmonary alveolar proteinosis.
View clinical trials →Clinical Trials
View all trials with filters →No actively recruiting trials found for Secondary pulmonary alveolar proteinosis at this time.
New trials open frequently. Follow this disease to get notified.
Specialists
View all specialists →No specialists are currently listed for Secondary pulmonary alveolar proteinosis.
Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Secondary pulmonary alveolar proteinosis.
Community
No community posts yet. Be the first to share your experience with Secondary pulmonary alveolar proteinosis.
Start the conversation →Latest news about Secondary pulmonary alveolar proteinosis
Disease timeline:
New recruiting trial: The CardioClip Study
A new clinical trial is recruiting patients for Secondary pulmonary alveolar proteinosis
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.What is the underlying cause of my PAP, and how will treating it affect my lungs?,Do I need whole lung lavage now, and how often might I need it repeated?,What oxygen levels should prompt me to go to the emergency room?,Are there any clinical trials for secondary PAP that I might qualify for?,How will we monitor whether my lung disease is getting better or worse over time?,Are there any activities or exposures I should avoid to protect my lungs?,Should I be referred to a center that specializes in rare lung diseases?
Common questions about Secondary pulmonary alveolar proteinosis
What is Secondary pulmonary alveolar proteinosis?
Secondary pulmonary alveolar proteinosis (secondary PAP) is a rare lung disease where a fatty, protein-rich substance called surfactant builds up inside the tiny air sacs of the lungs (called alveoli). This buildup makes it very hard for oxygen to pass from the lungs into the bloodstream. Unlike the primary form of this disease, secondary PAP is caused by another underlying condition — most often a blood disorder, a weakened immune system, certain infections, or exposure to toxic dusts or chemicals. Common underlying causes include leukemia, lymphoma, myelodysplastic syndrome, HIV infection, a
How is Secondary pulmonary alveolar proteinosis inherited?
Secondary pulmonary alveolar proteinosis follows a sporadic inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.