Familial tendency is not seen in
**Core Concept**
Familial tendencies refer to the genetic predisposition of certain diseases or conditions to occur within families. This concept is essential in understanding the etiology and management of various disorders, particularly those with a strong genetic component.
**Why the Correct Answer is Right**
Familial tendencies are indeed seen in several conditions, such as hypertension, diabetes mellitus, and certain types of cancer. However, not all diseases exhibit a clear familial pattern. For instance, acquired conditions like pulmonary tuberculosis, which can be caused by environmental factors, do not typically show a familial tendency.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because certain types of hypertension, such as primary aldosteronism, can exhibit a familial tendency due to genetic mutations affecting hormone regulation.
**Option B:** Incorrect because diabetes mellitus, particularly type 2, has a strong familial component, with genetic factors contributing to the risk of developing the disease.
**Option C:** Incorrect because certain types of cancer, such as breast and ovarian cancer, have a well-established familial component, often linked to genetic mutations in tumor suppressor genes or oncogenes.
**Option D:** Correct because pulmonary tuberculosis is an acquired condition primarily caused by environmental factors, such as exposure to Mycobacterium tuberculosis, and does not exhibit a clear familial tendency.
**Clinical Pearl / High-Yield Fact**
It's essential to distinguish between familial and acquired conditions to provide appropriate genetic counseling and management strategies for patients and their families.
**Correct Answer:** D. Pulmonary tuberculosis.