Many respiratory diseases present with similar symptoms, which is why getting an accurate diagnosis is not always so straightforward. For example, early symptoms of idiopathic pulmonary fibrosis including coughing, fatigue, and shortness of breath often occur with other lung diseases. According to a survey by the Pulmonary Fibrosis Foundation, about half of patients with interstitial lung disease are misdiagnosed at least once.
Why is a Delay in an Accurate Diagnosis Common?
There are several reasons why some people may have a delay in diagnosis including:
Symptoms are sometimes subtle
In the early stages of IPF, symptoms may be mild or subtle. Some people may have symptoms that are also associated with other conditions, such as connective tissue diseases or other chronic lung conditions.
Typical diagnostic tests are not always definitive
In patients that have other lung diseases, such as COPD, standard diagnostic tests are often helpful. In IPF, diagnostic tests, such as a pulmonary function test, chest x-ray, and arterial blood gas, may detect abnormalities and lung damage. But they often do not indicate a definitive diagnosis.
Lack of expertise
Idiopathic pulmonary fibrosis is not as common as other types of lung diseases, such as asthma and emphysema. Not every primary care doctor or internist is familiar with the subtleties of the disease. For instance, a physician that only sees patients with interstitial lung disease on occasion may not spot the features of the disease on an imaging scan. Also, IPF is only one type of interstitial lung disease. There are also other subtypes of ILD, which can make distinguishing between forms of the disease difficult.
Conditions That May be Mistaken for IPF
It’s not uncommon, especially early on for idiopathic pulmonary fibrosis to be misdiagnosed with one of the following conditions:
Sarcoidosis
Sarcoidosis is considered a connective tissue disease, which causes inflammation in the affected organs. Various organs can be affected including the skin, lymph nodes, and liver. When sarcoidosis affects the lungs, symptoms can mimic idiopathic pulmonary fibrosis including shortness of breath and a dry cough.
Chronic obstructive pulmonary disease
COPD is a term used for a group of obstructive lung diseases. Symptoms often includeshortness of breath that gets progressively worse, coughing, and fatigue. A cough is often dry in people with IPF while a productive cough in people with COPD is more common. COPD is so much more common than IPF, and early symptoms may be similar, which may lead to a misdiagnosis.
Scleroderma
Scleroderma is a connective tissue disease that causes tightening and hardening of the connective tissue and skin. Some people have lung involvement, which can cause coughing, decreased exercise tolerance, and shortness of breath.
Early Diagnosis is Vital
Some treatment recommendations may overlap between lung diseases, such as the need for oxygen and pulmonary rehabilitation classes. But certain treatments may also be different. For example, medications prescribed may be different for IPF than other lung diseases.
Getting an accurate diagnosis is vital to managing idiopathic pulmonary fibrosis as effectively as possible. Although there is currently no cure for IPF, there are medications and treatments, which may slow the progression of the illness. The earlier treatment can start the better.
Content written by Dr. Jeremy Feldman, an expert in Idiopathic Pulmonary Fibrosis, with contributions by MaryAnn DePietro, B.S. CRT, a licensed respiratory therapist.