Differential Diagnosis for Fever with Chills

Single Most Likely Diagnosis

• Malaria: This is a common cause of intermittent fever with chills, especially in endemic areas. The cyclical nature of the fever, corresponding to the life cycle of the parasite, is a hallmark of this disease.

Other Likely Diagnoses

• Pyelonephritis or Urinary Tract Infection (UTI): These infections can cause recurrent fever and chills, especially if the infection is not fully cleared or if there is an underlying anatomical issue.
• Pneumonia: Certain types of pneumonia, especially those caused by atypical bacteria, can present with intermittent fever and chills.
• Influenza: Although more commonly associated with a constant fever, influenza can sometimes cause fever that spikes and then resolves, accompanied by chills.
• Tuberculosis (TB): While TB can cause a variety of symptoms, intermittent fever with chills, especially in the afternoon, is a classic presentation.

Do Not Miss Diagnoses

• Endocarditis: Infective endocarditis can cause intermittent fever and may be accompanied by chills. It's a life-threatening condition that requires prompt diagnosis and treatment.
• Sepsis: Any source of infection leading to sepsis can present with fever and chills. Early recognition is crucial for survival.
• Meningitis: Although typically presenting with a constant fever, meningitis can occasionally cause intermittent fever spikes with chills, and it is critical to diagnose and treat promptly.

Rare Diagnoses

• Relapsing Fever: Caused by certain species of Borrelia, this condition is characterized by recurring episodes of fever and chills, separated by periods of normal temperature.
• Brucellosis: A zoonotic infection that can cause undulant fever, characterized by a rising and falling temperature pattern, often accompanied by chills.
• Lymphoma: Certain types of lymphoma can cause intermittent fever, known as Pel-Ebstein fever, which may be accompanied by chills.

Each of these diagnoses has a unique set of additional symptoms and risk factors that can help guide further investigation and diagnosis. A thorough medical history, physical examination, and appropriate laboratory tests are essential for determining the underlying cause of fever with chills.