A patient presents with watery diarrhea, abdominal cramps, and nausea after consuming contaminated water from a stream during a camping trip. Laboratory tests reveal oocysts in the stool sample. Which of the following parasites is most likely responsible for this infection?

Correct Answer: C

Rationale: The patient is likely infected with Cryptosporidium parvum based on the symptoms of watery diarrhea, abdominal cramps, and nausea after consuming contaminated water. Cryptosporidium is a protozoan parasite that can be transmitted through contaminated water sources, such as streams. Laboratory tests revealing oocysts in the stool sample further support the diagnosis of Cryptosporidium infection, as these oocysts are characteristic of this parasite. Giardia lamblia is another common protozoan parasite that can cause similar symptoms but is usually associated with more foul-smelling, greasy diarrhea. Entamoeba histolytica causes amoebic dysentery, which presents with bloody diarrhea and abdominal pain. Cyclospora cayetanensis also causes watery diarrhea, but it is usually associated with foodborne outbreaks rather than waterborne transmission.

Correct Answer: A

Rationale: The presentation described, involving multiple grouped vesicles on an erythematous base in the genital area, is classic for herpes simplex genitalis. This condition is caused by the herpes simplex virus (HSV) and is characterized by recurrent outbreaks of painful vesicles in the genital or perianal area. The history of similar lesions occurring during periods of stress is also suggestive of herpes simplex virus reactivation. Genital warts (condyloma acuminata) typically present as painless, fleshy growths in the genital area caused by human papillomavirus (HPV). Syphilis manifests as a painless ulcer known as a chancre, which is not described in the presentation. Molluscum contagiosum presents with pearly, dome-shaped papules with central umbilication, rather than vesicles.

Correct Answer: C

Rationale: The nurse's primary responsibility in responding to a patient's questions about their diagnosis and treatment options is to listen actively and provide accurate, honest, and comprehensive answers. This approach helps build trust between the patient and the healthcare team, allows the patient to make informed decisions about their care, and ensures that the patient understands their condition and the recommended treatment plan. Providing vague answers or ignoring the patient's questions can lead to confusion, anxiety, and mistrust, which can hinder the patient's overall care and recovery. Referring the patient to the physician for all questions may be appropriate for certain medical inquiries, but the nurse plays a crucial role in educating and supporting the patient throughout their healthcare journey.

Correct Answer: C

Rationale: Mastitis is an infection of the breast tissue that may occur in postpartum clients. When a postpartum client exhibits signs of mastitis, including breast tenderness, erythema, and warmth, it is crucial to notify the healthcare provider immediately. Prompt medical evaluation is necessary to determine the appropriate treatment plan, which may include antibiotics. Delay in treatment can lead to complications, such as abscess formation. Encouraging the client to continue breastfeeding and applying warm compresses may provide some relief but do not address the underlying infection. Administering oral antibiotics would require a prescription from the healthcare provider, hence notifying the provider is the most appropriate initial nursing action in this situation.

Correct Answer: A

Rationale: The presentation described in the question is most consistent with anterior uveitis. Anterior uveitis, also known as iritis, is characterized by redness, pain, and photophobia in the affected eye. Slit-lamp examination typically reveals ciliary injection (reddening of the conjunctiva and episclera), corneal edema, and a mid-dilated pupil with a fixed reaction to light (miosis). This occurs due to inflammation within the anterior chamber of the eye involving the iris and ciliary body.

Correct Answer: D

Rationale: Speaking up on behalf of the patient to ensure their needs are met is a key action that demonstrates advocacy by the nurse. Advocacy involves actively supporting and safeguarding the rights of the patient, ensuring that their best interests are being considered within the healthcare system. This may include advocating for appropriate treatment, services, resources, or respect for the patient's autonomy and decision-making. By speaking up for the patient, the nurse is acting as their voice and championing their well-being.

Correct Answer: B

Rationale: Mastitis is typically caused by bacterial infection, with predisposing factors including milk stasis (I) and nipple trauma (II). Milk stasis occurs when milk is not effectively removed from the breast, leading to a build-up that can block ducts and predispose to infection. Nipple trauma, such as cracks or damage, can provide entry points for bacteria to infect the breast tissue. Factors like using alcohol in cleaning nipples (III) and the baby's sitting position (IV) are not directly associated with the development of mastitis.

Correct Answer: C

Rationale: Humoral immunity is primarily responsible for protecting against infections by pathogens like viruses. In the case of the hepatitis B virus (HBV), the individual is exposed to the virus and develops immunity, which is typically mediated by antibodies produced by B cells. These antibodies circulate in the blood and can neutralize the virus, preventing future infections. This type of immunity is known as humoral immunity, as it involves the production of antibodies that target specific antigens, such as those present on the surface of the hepatitis B virus. In contrast, passive immunity is when antibodies are transferred from an external source, innate immunity provides immediate, non-specific defenses against pathogens, and cell-mediated immunity involves the activation of T cells to combat intracellular pathogens.

Correct Answer: C

Rationale: In a pregnant patient with suspected pulmonary embolism (PE), the most appropriate imaging modality for evaluation is contrast-enhanced computed tomography (CT) pulmonary angiography. This imaging technique has been shown to be safe for the fetus when necessary, especially if the benefits of making a diagnosis outweigh the minimal risks associated with radiation exposure. It provides quick and accurate detection of PE with high sensitivity and specificity.