Differential Diagnosis
The patient's symptoms of generalized lymphadenopathy, intermittent low-grade fever, and a cystic lesion in the spleen can be approached by considering the following categories:
Single Most Likely Diagnosis
- Tuberculosis (TB): TB can cause generalized lymphadenopathy, intermittent low-grade fever, and can affect the spleen, although splenic involvement is less common. The presence of these symptoms, especially in regions where TB is prevalent, makes it a strong candidate for the diagnosis.
Other Likely Diagnoses
- Lymphoma: Both Hodgkin's and non-Hodgkin's lymphoma can present with generalized lymphadenopathy and systemic symptoms like low-grade fever. Splenic involvement is common in lymphoma, which could explain the cystic lesion.
- Sarcoidosis: This condition can cause lymphadenopathy and systemic symptoms. While less common, it can also involve the spleen, although cystic lesions are not typical.
Do Not Miss Diagnoses
- Kala Azar (Visceral Leishmaniasis): Although less likely in some regions, Kala Azar can cause significant morbidity and mortality if not treated. It presents with fever, weight loss, and splenomegaly, which could be consistent with the cystic lesion in the spleen if due to secondary infection or other complications.
- Malaria: Certain types of malaria, especially those caused by Plasmodium vivax or Plasmodium ovale, can have a more prolonged course with intermittent symptoms. Splenic involvement is common, and while cystic lesions are not typical, the diagnosis of malaria is critical due to its potential severity and the availability of effective treatment.
Rare Diagnoses
- Castleman Disease: A rare disorder that can cause lymphadenopathy and systemic symptoms. It can involve the spleen, although this is less common.
- Brucellosis: A zoonotic infection that can cause fever, lymphadenopathy, and splenomegaly. It's less common but should be considered in individuals with exposure to animals or their products.
- Histoplasmosis: A fungal infection that can cause lymphadenopathy, fever, and splenic involvement, particularly in immunocompromised individuals or those exposed to the fungus in endemic areas.