Brief Answer: Infections, malignant conditions or systemic cause Detailed Answer: Hello ma'am and welcome. Thank you for writing to us. Cervical lymphadenapathy can have numerous causes to it, I would first like to start by listing these causes out for you, so you can relate to them and accordingly narrow down the search. They are: -Infections (eg. tuberculosis, chicken pox, viral respiratory infections, brucellosis, syphilis, etc.). Each infection has its specific presentation, so finding an infection based on your presentation would not be too difficult. But before this it would be important to confirm/rule out the presence of an infection in your body. This can be done by simply checking on your leukocyte level -Malignant conditions (can be ruled out with the help of that lymph node biopsy, which has already been conducted) -Other systemic conditions: This list of conditions are a little more complex to diagnose. But once infections and malignant conditions are ruled out, we will have to consider this group of conditions Weight gain could be present due to various reasons, irrelevant to the current condition as well, so this would be non-specific, although I really appreciate your thoroughness in trying to provide us with as much information as possible. But, it is also important to note that in malignant conditions, there is usually weight loss more often than weight gain. I hope you found my response informative ma'am. Please feel free to write back to me for any further clarifications, I would be more than happy to help you. Best wishes.

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