blood iron content. Immunosuppression Immunosuppressants are often used to treat autoimmune diseases, such as lupus. When individuals undergo treatment with immunosuppressants such as glucocorticoids, their bodies' defenses are lowered. As a result, exposure to C. canimorsus is more infectious in these individuals than in healthy individuals. Immunosuppressed patients make up about 5% of individuals presenting with C. canimorsus symptoms. Symptom onset and clinical manifestations Symptoms appear within 1–8 days after exposure to C. canimorsus but usually present around day 2. Symptoms range from mild, flu-like symptoms to full-blown fulminant sepsis. Individuals often complain of any combination of: fever, vomiting, diarrhea, malaise, abdominal pain, myalgia, confusion, dyspnea, headaches, and skin rashes such as exanthema. More severe cases of endocarditis, disseminated intravascular coagulation, and meningitis have been reported. Prior treatment with methylprednisolone has been shown to prolong bacteremia in these infections, which enables the progression of endocarditis. Differential diagnosis Diagnosing infections with C. canimorsus can be difficult. Common practice for culturing isolates is to keep agar plates for one week; sometimes, cultures of C. canimorsus are not visible at that point due to slow growth or inappropriate media. C. canimorsus requires very specific culture media and conditions; enriched media are necessary. C. canimorsus displays enhanced growth in high concentrations of carbon dioxide, so culturing the bacteria in candle extinction jars or carbon dioxide incubators is necessary. To diagnose this bacillus, certain reactions may be tested. The bacterium should test positive for catalase and oxidase, arginine dihydrolase, maltose, and lactose. It should test negative for nitrate reduction, urease, and H2S production. C. canimorsus can be distinguished from other Gram-negative bacteria by testing negative for inulin and sucrose. Due to the relatively slow growth of this bacterium, diagnosis often relies upon the clinician having knowledge that the patient was previously in contact with a canine or feline. Once aware of this, clinicians can request that agar plates be kept longer than one week to ensure proper isolation of the bacterium. Sometimes, even these methods fail. Cases have been noted where cultures repeatedly came up negative for C. canimorsus, only to determine its presence with 16S rRNA gene sequencing. PCR assays of species-specific genes may also be beneficial. For individuals presenting with meningitis, C. canimorsus can be diagnosed with a cerebrospinal fluid Gram stain. These methods are more costly, but are the best way to ensure species-level identification. Isolates are usually obtained from blood cultures