Table 1: Laboratory evaluation of the synovial fluid and blood performed in a 12-year-old boy with X-linked agammaglobulinemia and recurrent knee effussions over a period of 5 years.

Lab investigations04/201003/200808/200703/200607/2005

Synovial fluid WBC (cells/mm3)11030,96027,00040,000220
Synovial fluid culture Neg NegNegNegNeg
Crypto/Cocci Ag/fungal stain and Cx Neg NegNegNegNeg
Atypical mycobacterium/mycoplasmas/ureaplasma Neg NegNegNegNeg
AFB Neg Negnegnegneg
ESR mm/hr-CRP mg/dL60/5.141/4.130/13.534/7.540/2.3
Blood culture and viral culturesNegNegNegNegNeg