Order additional specialized testing such as advanced autoimmune panels and functional MRI, as the extensive but unremarkable basic workup suggests a rare medical condition requiring more targeted investigation.

Continuing to order tests after extensive unremarkable workups reinforces medical reassurance-seeking and delays appropriate treatment. If specific clinical indicators arise, targeted testing may be warranted, but exploratory testing is not helpful.

Diagnose fibromyalgia based on the pattern of diffuse pain, fatigue, and GI symptoms, as this constellation meets the diagnostic criteria and would allow targeted treatment with duloxetine or pregabalin.

Fibromyalgia has specific diagnostic criteria (widespread pain index + symptom severity) and is a medical diagnosis, not within the PMHNP's primary scope. The PMHNP's role is assessing for comorbid psychiatric conditions driving or amplifying the symptoms.

Assess for somatic symptom disorder while validating her experience, screening for comorbid depression, anxiety, and trauma history as potential drivers of somatic amplification.

The PHQ-15 is a somatic symptom severity screener (validated cutoffs: >=10 medium, >=15 high). A score of 19 indicates high somatic symptom burden. Multiple unexplained somatic complaints with extensive negative workups raise concern for somatic symptom disorder. The critical clinical skill is validating the experience ("your symptoms are real") while redirecting from a purely medical explanation to a biopsychosocial model. Trauma screening is essential — adverse childhood experiences strongly predict adult somatization. Assess for comorbid depression and anxiety, which drive somatic amplification, as well as health-related behaviors and beliefs, and functional impairment.

Reassure her that all tests are normal and nothing is medically wrong, then recommend relaxation techniques and stress management strategies to address the likely psychosomatic origin of her symptoms.

Telling a patient with 18 months of real symptoms that "nothing is wrong" invalidates their experience and damages the therapeutic alliance. This approach mirrors what has already failed with prior providers.