The 4 Types of Emphysema
Emphysema is one of the possible manifestations of chronic obstructive pulmonary disease (COPD). They’re characterized by damage to the lining of the alveoli, which hinders the breathing process. According to the American Lung Association, the condition takes years to develop symptoms and can’t be cured. Here are the main types of emphysema.
It isn’t uncommon for this condition to be confused with chronic bronchitis, but as we have already told you, there are several differences between the two. The progression of the condition is progressive, so that patients must deal with its sequelae over the years.
Types of emphysema by their causes
The first division of the types of emphysema is found according to its causes. It is true that it isn’t the category preferred by specialists, but it should be taken into account. We thus highlight the following varieties:
- Hereditary pulmonary emphysema: Although it only affects a small group of patients, the evidence in this regard indicates that alpha-1 antitrypsin deficiency is a determinant at the time of developing emphysema. This explains why cases are reported in non-smokers. Tobacco, however, is the main trigger.
- COPD emphysema: In these cases there’s no alpha-1 antitrypsin deficiency, although there is an excessive accumulation of proteases. This destroys the elasticity of the alveoli.
Main types of emphysema
The classical medical literature considers three types of emphysema, although we have included more variants, because some cases cannot be grouped with the others. In general, there are no differences in prognosis or evolution between them.
1. Centroacinar
According to researchers, centroacinar emphysema is the most common manifestation of this condition. It is also known as proximal or centrilobular and is distinguished because it affects the upper part of the lungs.
Most develop in smokers, so cigarette smoke is thought to be their main trigger. Passive and active exposure can generate it.
This type of emphysema also has an intrinsic division. Studies have identified three subtypes, which are simply referred to as types A, B, and C. It can develop through interaction with smoke particles from other non-tobacco sources, such as cooking with firewood or working in coal mines.
2. Panacinar
This is also known as panlobular emphysema. It isn’t known what can cause it, although some experts point to alpha-1 antitrypsin deficiency, Ritalin ® abuse, and Swyer’s syndrome.
In this case, it affects the lower half of the lungs and produces a uniform mass of air spaces in the alveoli. This type is, in turn, divided into two subtypes, according to their distribution.
3. Paraseptal
Also called distal emphysema. Evidence suggests that this variant is more common in men over 60 years of age who are smokers. This time, the episodes are concentrated around the septum and pleura, with a higher incidence in the upper part.
This type does not cause symptoms. This makes it difficult to diagnose, at least from a clinical point of view. Sometimes it develops as a sequel to a pneumothorax.
4. Irregular
Less common than the above types of emphysema, some patients also develop an irregular manifestation of emphysema. It’s distinguished by healing processes, which has led some to call it cicatricial or para-scar emphysema.
In turn, other minor types of the condition are combined emphysema (several types at the same time), bullous, senile, interstitial and lobular. Occasionally, patients develop pulmonary fibrosis in the company of one of these variants.
Types of emphysema reveal its severity
Although it’s often ignored, COPD is one of the diseases that causes the highest number of deaths annually. In fact, and following data from the World Health Organization (WHO), it’s the third leading cause of death worldwide, with a total of 3.23 million deaths in 2019 alone.
Considering that its main risk factor is tobacco smoke, we highly recommend that you reduce or completely give up your tobacco intake. Living a healthy life, avoiding respiratory irritants, and getting vaccinated against infections can also tip the balance in your favor.
- Araki, T., Nishino, M., Zazueta, O. E., Gao, W., Dupuis, J., Okajima, Y., … & Hatabu, H. Paraseptal emphysema: prevalence and distribution on CT and association with interstitial lung abnormalities. European journal of radiology. 2015; 84(7): 1413-1418.
- Molfino, N. A. Hereditary Pulmonary Emphysema. In Emery and Rimoin’s Principles and Practice of Medical Genetics and Genomics. 2020; 361-403.
- Takahashi, M., Yamada, G., Koba, H., & Takahashi, H. (2012). Classification of centrilobular emphysema based on CT-pathologic correlations. The open respiratory medicine journal. 2012; 6: 155.
- Takahashi, M., Fukuoka, J., Nitta, N., Takazakura, R., Nagatani, Y., Murakami, Y., … & Murata, K. Imaging of pulmonary emphysema: a pictorial review. International journal of chronic obstructive pulmonary disease. 2008; 3(2): 193.
