Differential Diagnosis for Young Woman with Severe Sweats

Single Most Likely Diagnosis

• Opioid Withdrawal: The patient's history of IV methamphetamine use and severe sweats without fever suggests opioid withdrawal, as methamphetamine users may also use opioids. The negative TB test and lack of fever make infectious causes less likely, pointing towards a withdrawal syndrome.

Other Likely Diagnoses

• Infectious Endocarditis: Despite the negative TB test, infectious endocarditis is a consideration in IV drug users, and severe sweats can be a symptom. Labs pending may reveal signs of infection or inflammation.
• Hypoglycemia or Hyperglycemia: IV drug users may have poor dietary habits, increasing the risk of blood sugar imbalances, which can cause sweating.
• Anxiety or Panic Disorder: The stress of withdrawal or the psychological effects of drug use could contribute to anxiety or panic disorders, manifesting as severe sweats.

Do Not Miss Diagnoses

• Sepsis: Although the patient does not have a fever, sepsis can present atypically, especially in drug users whose immune response may be altered. It's crucial to consider sepsis due to its high mortality rate if missed.
• Meningitis or Encephalitis: These conditions can present with non-specific symptoms such as sweating and can be deadly if not promptly treated. A high index of suspicion is required, especially in IV drug users who may be at higher risk for infectious diseases.
• Thyroid Storm: This is a life-threatening condition that requires immediate recognition and treatment. Although less common, it could present with severe sweats among other symptoms.

Rare Diagnoses

• Pheochromocytoma: A rare tumor of the adrenal gland that can cause episodes of sweating, hypertension, and tachycardia. It's an unlikely cause but should be considered if other diagnoses are ruled out.
• Neuroleptic Malignant Syndrome (NMS): Although rare, NMS can occur in response to certain medications or drug withdrawal, leading to severe sweating, fever, and muscle rigidity. The absence of fever in this case makes it less likely but not impossible.
• Autoimmune Disorders: Certain autoimmune conditions, like lupus or rheumatoid arthritis, can present with non-specific symptoms such as sweats. These would be considered if other diagnoses are excluded and there are additional suggestive symptoms or lab findings.