Which symptom is indicative of the fulminant stage in a client with inhalation anthrax?

The fulminant stage of inhalation anthrax is characterized by severe, acute symptoms that emerge rapidly following the initial infection. Mediastinitis, which refers to inflammation of the mediastinum (the area in the chest located between the lungs), is a critical symptom during this stage. Inhaling anthrax spores can lead to severe respiratory distress and can result in extensive involvement of the mediastinum and surrounding structures, indicating a more advanced and dangerous progression of the disease.

In this fulminant phase, patients often present with severe respiratory failure and systemic infection, which can escalate quickly. Mediastinitis in this context signifies that the infection has progressed significantly, which is consistent with the serious nature of inhalation anthrax. This symptom aligns with the severe complications that can arise in infected individuals, differentiating it from milder symptoms often seen in earlier stages, such as fever or dry cough, which may not necessarily indicate the fulminant severity of the condition.