In Castillo v. August, 248 S.W.3d 874 (Tex. App.--El Paso 2008, no pet.), Castillo underwent spinal surgery, was subsequently transferred to a rehabilitation facility under the care of Dr. August, and developed a staph infection in the surgical site and meningitis. Castillo sued Dr. August and other defendants alleging that Dr. August had a duty to observe and monitor her incision for any sign of infection and that his failure to do so resulted in the staph infection and life-threatening meningitis. Id. at 878. The expert report opined that Dr. August should have personally and vigilantly monitored Castillo's status because she had presented upon admission to the rehabilitation facility with signs and symptoms of infection and that he should have identified, examined, diagnosed, and taken measures to treat the infection. Id. at 882. As to causation, however, the expert report by Dr. Pacheco stated only that "Dr. August's breach of the standard of care 'caused Ms. Castillo to suffer the meningitis and caused the need to remove the hardware that the surgeon had implanted in Ms. Castillo's spine--given the advanced and uncontrolled state of the infection in her back.'" Id. Holding that the expert report was deficient concerning causation, the Castillo court held: "Dr. Pacheco does not adequately link Dr. August's actions to Ms. Castillo's subsequent "raging infection" and staph meningitis. His narrative of events does not discuss delusional behavior, meningitis, or a subsequent surgery to debride the wound and remove the hardware. Nor does he explain how the infection in her back caused the meningitis. While a claimant is not required to conclusively prove her case through a preliminary expert report, the report may not merely state conclusions about any of the elements. Dr. Pacheco's expert report requires us to infer causation, which, under the "four corners" rule, we are not permitted to do." Id. at 882-83 . In sum, the plaintiff underwent spinal surgery and was subsequently transferred to a rehabilitation facility under the care of Dr. August. The plaintiff developed a staph infection in the surgical site and meningitis. She sued Dr. August and other defendants alleging that Dr. August had a duty to "observe and monitor" her incision for any sign of infection and that his failure to do so resulted in the staph infection and life-threatening meningitis. The expert report opined that the standard of care required Dr. August to personally and vigilantly monitor the plaintiff's status because she had presented upon admission with signs and symptoms of infection. The standard of care also required that he identify, examine, diagnose, and take measures to treat the infection. Id. at 882. The trial court denied Dr. August's motion to dismiss because the report did not adequately delineate either the standard of care or how a breach thereof harmed the plaintiff. Id. at 878. Noting that causation could not be inferred, we concluded that the report did not adequately address causation because it did not explain how the staff infection caused the meningitis. Id. at 882-83.