Rocky Mountain spotted fever, Panama.
Bottom Line: We describe a fatal pediatric case of Rocky Mountain spotted fever in Panama, the first, to our knowledge, since the 1950s.Diagnosis was established by immunohistochemistry, PCR, and isolation of Rickettsia rickettsii from postmortem tissues.Molecular typing demonstrated strong relatedness of the isolate to strains of R. rickettsii from Central and South America.
Affiliation: Hospital del Niño, Panama City, Panama.
We describe a fatal pediatric case of Rocky Mountain spotted fever in Panama, the first, to our knowledge, since the 1950s. Diagnosis was established by immunohistochemistry, PCR, and isolation of Rickettsia rickettsii from postmortem tissues. Molecular typing demonstrated strong relatedness of the isolate to strains of R. rickettsii from Central and South America.
Related in: MedlinePlus
Mentions: Immunohistochemical evaluation of formalin-fixed, paraffin-embedded tissues that used an immunoalkaline phosphatase technique demonstrated spotted fever group rickettsial antigens associated with rickettsia-like cells in vascular endothelium of multiple tissues, including heart (Figure 1), lung, adrenal gland, and kidney. Serum collected on the day of death had immunoglobulin (Ig) G and IgM microimmunofluoresence antibody titers of 2,048 to R. rickettsii antigen. DNA samples prepared from frozen brain, liver, lymph node, and spleen autopsy specimens were tested by PCR as described previously (7). When amplified, a 208-bp fragment of the conserved 17-kDa Rickettsia antigen gene showed spotted fever rickettsial DNA was present in all autopsy tissues. An OmpA gene fragment (70–602 nt) was amplified from brain and lymph node tissues (GenBank accession nos. DQ002503 and DQ002504). DNA sequencing of the ompA amplicons demonstrated that their nucleotide sequences were identical to each other and had 100% sequence similarity to the homologous ompA fragment of R. rickettsii strain Sheila Smith, isolated from a patient in Montana. An isolate of R. rickettsii (designated Panama 2004) was obtained from brain tissue in Vero E6 cells; its OmpA gene fragment (DQ164838) had 100% nucleotide sequence similarity to the reference sequence of R. rickettsii type strain Sheila Smith. R. rickettsii from Panama is similar to the other R. rickettsii strains circulating in Central and South America but differs from strain Sheila Smith in at least 1 locus containing tandemly repeated sequences (Figure 2).