A 35-year-old woman presents with irregular menstrual cycles, hirsutism, and acne. Which of the following conditions is most likely to be associated with these symptoms?

Correct Answer: A

Rationale: Polycystic ovary syndrome (PCOS) is a common hormonal disorder in women of reproductive age. The classic symptoms of PCOS include irregular menstrual cycles, hirsutism (excess hair growth in a male pattern), and acne. Women with PCOS often have enlarged ovaries with multiple small cysts. Other common features include obesity, insulin resistance, and infertility. Endometriosis is characterized by the presence and growth of endometrial-like tissue outside the uterus, leading to symptoms such as pelvic pain and infertility. Ovarian cancer usually presents with nonspecific symptoms and is less likely in a young woman with these specific symptoms. Uterine fibroids are benign tumors that can cause heavy menstrual bleeding and pelvic pressure but are less likely to be associated with hirsutism and acne.

Correct Answer: B

Rationale: Adenomyosis is a condition characterized by the presence of endometrial tissue within the myometrium (muscle wall) of the uterus. It can present with symptoms such as cyclic pelvic pain, dysmenorrhea (painful periods), and infertility. On pelvic examination, the uterus may be retroverted (tilted backward) and enlarged due to the presence of adenomyotic nodules within the uterine muscle. Adenomyosis can also cause heavy menstrual bleeding (menorrhagia). Endometriosis, on the other hand, involves the presence of endometrial tissue outside the uterus and can cause similar symptoms but is less likely to result in uterine enlargement or retroversion. Leiomyomas (uterine fibroids) are benign tumors of the uterine muscle and can also cause pelvic pain and abnormal uterine enlargement but are less likely to be associated with dysmenorrhea and infertility

Correct Answer: B

Rationale: During the acute phase response, C-reactive protein (CRP) primarily serves to activate the complement system. CRP binds to phosphocholine on the surface of pathogens, allowing for the activation of the classical pathway of the complement system. This leads to the recruitment of immune cells, opsonization of pathogens, and enhancement of phagocytosis. The activation of the complement system by CRP plays a crucial role in the host defense against infections, aiding in the elimination of pathogens and the resolution of inflammation.

Correct Answer: C

Rationale: Dendritic cells play a critical role in initiating adaptive immune responses by capturing antigens from pathogens, migrating to lymphoid organs, and presenting these antigens to naïve T cells. This activation of naïve T cells by dendritic cells is essential for the adaptive immune system to generate specific immune responses against pathogens. Dendritic cells act as professional antigen-presenting cells, which are specialized to capture, process, and present antigens to T cells, thereby facilitating the activation of T cells and the coordination of adaptive immune responses, such as the production of specific antibodies and the generation of memory T cells.

Correct Answer: A

Rationale: The development of autoantibodies such as antinuclear antibodies (ANA) and anti-double-stranded DNA (anti-dsDNA) antibodies in systemic lupus erythematosus (SLE) is primarily attributed to a loss of self-tolerance. Self-tolerance refers to the immune system's ability to recognize and differentiate self-antigens from foreign antigens. In individuals with SLE, there is a breakdown in immune tolerance mechanisms, leading to the production of autoantibodies against self-antigens like nuclear components (e.g., DNA, RNA, histones). This loss of self-tolerance results in the immune system targeting and attacking its tissues, leading to the systemic inflammation and tissue damage characteristic of SLE. The presence of elevated levels of ANA and anti-dsDNA antibodies in this patient suggests an autoimmune response against nuclear material, further supporting the role of self-tolerance breakdown in SLE