In a client diagnosed with pregnancy-induced hypertension (PIH), what symptom should the nurse instruct the client to report immediately?

In a client diagnosed with pregnancy-induced hypertension (PIH), blurred vision is a symptom that warrants immediate reporting. This symptom can indicate potential complications such as worsening hypertension or the development of conditions like preeclampsia or eclampsia. Blurred vision can result from increased intracranial pressure, swelling in the retina, or other changes associated with hypertension that could have serious consequences for both the mother and the fetus.

While backache, constipation, and increased urine output may be relevant to the client's overall health or comfort during pregnancy, they are not typically considered as urgent indicators of deteriorating condition related to hypertension. Specifically, backache is common during pregnancy due to physical changes and does not usually signify an immediate threat. Constipation may arise from dietary changes or hormonal shifts but typically does not indicate an acute medical issue. Increased urine output could also be part of normal pregnancy-related changes and may not necessarily correlate with worsening hypertension. Thus, among the options provided, blurred vision stands out as a critical symptom that should be reported without delay.