Paradoxical worsening of tuberculosis in a heart-lung transplant recipient.

We report on a heart-lung transplant recipient who presented with pulmonary tuberculosis (TB) 2.5 months after transplantation and then developed a paradoxical reaction after 4 months of adequate anti-TB treatment. She eventually recovered with anti-TB and high-dose steroid treatments. METHODS: Using sequential bronchoalveolar lavages, we assessed the inflammatory response in the lung and investigated the alveolar immune response against a Mycobacterium tuberculosis antigen. RESULTS: The paradoxical reaction was characterized by a massive infiltration of the alveolar space by M. tuberculosis antigen-specific CD4(+) T cells and by the presence of a CD4(-)CD8(-) T lymphocyte subpopulation bearing phenotypic markers (CD16(+)/56(+)) classically associated with NK cells. CONCLUSION: This case report illustrates that even solid organ transplant recipients receiving intense triple-drug immune suppression may be able to develop a paradoxical reaction during TB treatment. Transplant physicians should be aware of this phenomenon in order to differentiate it from treatment failure.

Selective defect of anti-pneumococcal IgG in a patient with persistent polyclonal B cell lymphocytosis.

BACKGROUND: Persistent polyclonal B cell lymphocytosis (PPBL) is a rare condition characterized by increased IgM and large excess of B cells with an IgD(+) CD27(+) phenotype. In normal individuals, these cells play a central role in the defense against pneumococcal infection. So far, few studies have characterized humoral immune responses in PPBL patients. We therefore measured IgG directed against S. pneumoniae antigens in a 51 yr-old woman with PPBL before and after vaccination with a pneumococcal 23-valent polysaccharide vaccine. METHODS: Antibodies against pneumococcal antigens were measured first with an overall immunoassay using microplates coated with the 23-valent pneumococcal vaccine. A serotype-specific test was also performed according to the WHO consensus protocol. RESULTS: Despite a large number of IgD(+) CD27(+) cells, our patient had low baseline titers of IgG directed against pneumococcal antigens and did not significantly respond to a 23-valent polysaccharide vaccine against S. pneumoniae. On the contrary, she had good titers of IgG directed against tetanus toxoid. CONCLUSION: IgM(+) IgD(+) CD27(+) cells which accumulate in this patient with typical PPBL patient failed to perform IgG isotype switch after a polysaccharide vaccine. The potential mechanisms and relationships with the main features of PPBL are discussed. Further studies on a larger number of similar patients are needed.