I have symptoms of Legionnaires’, but the tests were negative?

My husband (57 yrs old) went to the ER with a 104oF temperature and shaking chills. He was diagnosed with pneumonia, but he had normal blood work, including WBC count. His condition deteriorated and he was intubated. He was critically ill and in ICU for 10 days and developed congestive heart failure. He recovered after heavy doses of antibiotics, including Rifampin, but tested negative for Legionella through urine and blood. They diagnosed him with suspected Legionnaires’ & sepsis based on clinical presentation.


Prior to the night he was hospitalized, I had an episode of shaking chills. While he was hospitalized, I had night sweats and a dry non-productive cough but no fever. After he was discharged, those symptoms persisted and I was extremely fatigued. I went for blood work and a chest X-ray. The X-ray and blood work were normal, except for mildly elevated liver enzymes. A week later,  my liver enzymes were normal, but Hep-B core AB, IgM was reactive. A follow up for Hep-B surface AB was nonreactive. The doctor suspected cross reactivity, and ordered repeat tests in 6 months. The Legionella pneumophila AB, IgG IF was 128.  Due to my husband’s condition, I was treated with a two week course of Levaquin, followed by more blood tests in 2-3 weeks. After 2 days on Levaquin, my cough and fatigue are gone, but night sweats continue. I have no weight loss or enlarged lymph nodes.


I was wondering if night sweats are associated with Legionnaires’? How likely is it that this could be due to Legionella? How long will it take for night sweats to go away once antibiotics were started? My husband and I both work together in a school.


Your husband’s symptoms are consistent with pneumonia including Legionnaire’s disease. The blood and urine test can be negative because the tests may not detect some Legionella subtypes (serogroups and species).

Your case is more difficult with respect to diagnosis. The chest X-ray is the test that confirms pneumonia, but your X-ray did not show pneumonia. Your IgG blood test suggests Legionnaires’ disease, but a second test 6-12 weeks after the first test is necessary for confirmation. I agree with your doctor to treat for Legionnaires’ disease. Symptoms of Legionnaires’ disease typically resolve after five days of antibiotics, if antibiotics are started early.

Follow-Up Questions:

I hope you don’t mind a few additional questions
1. Are night sweats a symptom of Legionnaires’?
2. You say symptoms typically resolve within five days if antibiotics are started early. I first had chills on Mar. 10th, cough/night sweats began March 14th, blood test done on March 26th and I received lab results & began antibiotics on April 6th. Is that early or should I expect it may take longer for night sweats to go away? My cough resolved in 48 hours.
3. My doctor is recommended repeat blood test in 2-3 weeks. Should the numbers quadruple in order for a positive diagnosis? Will that be long enough? I see you recommend 6-12 weeks.
4. Is this something we should inform the school about?

Follow-Up Reply:

Night sweats accompany the fever, so if fever resolves, so should the night sweats. Your doctor is well-informed. However, for Legionnaires’ disease the time of maximal seroconversion (technical lingo) is 6 to 12 weeks. No need to inform if your blood Legionella antibody titer is not elevated. Perhaps, your husband should have a repeat titer done also. Does he have a chronic underlying disease or does he smoke?

If none of your colleagues have contracted pneumonia recently, probably not a concern for your school. If your titer is elevated, feel free to email me again.