Question

An 80-year-old man presented to the emergency department with excruciating pain in his right forearm. He reported spending the previous night fishing in Corpus Christi Bay, where he accidentally pierced his right index finger with a live shrimp. Hemorrhagic bullae were present, extending from the hand to the upper arm. He also presented with confusion. The patient had a history of cirrhosis secondary to alcohol abuse. A Gram stain of the exudate showed a curved, gram-negative rod. Blood and wound cultures were obtained. The patient was admitted to the intensive care unit and was treated with oxygen, fluid resuscitation, and intravenous ceftriaxone and doxycycline (Doxy 100). On the fourth day of hospitalization, the patient markedly improved, answered questions appropriately. Wound culture confirmed the clinical diagnosis of a Gram negative curved bacillus infection. After five days in the intensive care unit, he was in stable condition and was transferred to a local hospital.

Which of the curved Gram negative bacillus is responsible for the disease this man is experiencing and why did you choose this one over others in this genera?

Answer 1

The curved Gram-negative bacillus causing the described symptoms is likely Vibrio vulnificus, based on the patient's exposure, symptoms, and response to treatment with ceftriaxone and doxycycline.

Step-by-step explanation:

The curved Gram-negative bacillus responsible for the disease in this case is most likely Vibrio vulnificus, which is commonly associated with wound infections from marine sources, especially in people with liver disease such as cirrhosis. The patient's history of spending time in Corpus Christi Bay, encountering marine life, and his subsequent symptoms of excruciating pain and confusion, coupled with the appearance of hemorrhagic bullae that extended from the hand to the upper arm, are indicative of Vibrio vulnificus infection. This bacterium is often treated with a combination of ceftriaxone and doxycycline, which aligns with the treatment the patient received, and his improvement suggests the correct pathogen was targeted.