A newly diagnosed teenage girl with scoliosis asks the nurse what is Cobb’s angle? You know the nurse’s answer is correct when she says this:

Choice A reason: Schizoaffective disorder’s active phase combines psychotic symptoms (delusions, hallucinations) with mood episodes, like major depression or mania, due to dysregulation in dopamine and serotonin pathways. Unlike schizophrenia, mood symptoms are prominent and persistent, defining the disorder’s diagnostic criteria during active phases, distinguishing it from schizophrenia’s primarily psychotic focus.

Choice B reason: Absence of delusions or hallucinations is incorrect for schizoaffective disorder’s active phase, which requires psychotic symptoms like those in schizophrenia. These arise from dopamine dysregulation in the mesolimbic pathway, making their presence essential for diagnosis, unlike this choice’s suggestion of their absence.

Choice C reason: More severe negative symptoms, like flattened affect or avolition, are characteristic of schizophrenia, not schizoaffective disorder’s active phase. Schizoaffective disorder emphasizes mood symptoms (depression or mania) alongside psychosis, with negative symptoms being less dominant, making this choice incorrect for its active phase.

Choice D reason: Anosognosia, or lack of insight into one’s illness, is common in schizophrenia but not a defining feature of schizoaffective disorder’s active phase. Schizoaffective disorder focuses on combined psychotic and mood symptoms, not necessarily more severe anosognosia, making this choice less relevant to its diagnostic criteria.

Choice A reason: Vomiting typically leads to metabolic alkalosis, not acidosis. It causes loss of hydrochloric acid from the stomach, reducing hydrogen ion concentration in the blood. This elevates blood pH above 7.45, as the body retains bicarbonate. The kidneys attempt to compensate by excreting excess bicarbonate, but this does not result in metabolic acidosis, making this choice incorrect.

Choice B reason: Thiazide diuretics increase sodium and water excretion, which can lead to mild metabolic alkalosis due to increased bicarbonate reabsorption in the kidneys. They do not cause a loss of bicarbonate or accumulation of acids, which are necessary for metabolic acidosis. Thus, this choice is incorrect as it does not contribute to an acidic blood state.

Choice C reason: Salicylate intoxication, such as from aspirin overdose, causes metabolic acidosis by increasing acid production. Salicylates stimulate the respiratory center, leading to hyperventilation and respiratory alkalosis initially, but they also disrupt mitochondrial function, causing lactic acid accumulation. This lowers blood pH below 7.35, meeting the criteria for metabolic acidosis, making this choice correct.

Choice D reason: Diarrhea results in significant bicarbonate loss through the stool, as the intestines secrete bicarbonate to neutralize gastric acid. This loss reduces the blood’s buffering capacity, lowering pH below 7.35, indicative of metabolic acidosis. The body may attempt to compensate via hyperventilation to reduce CO2, but the primary issue is bicarbonate depletion, making this choice correct.