ABSTRACT
We present a 19-year-old woman, a case of Lemierre syndrome, who presented with fever, sore throat, and left shoulder pain. Imaging revealed a thrombus in the right internal jugular vein, multiple nodular shadows below both pleura with some cavitations, right lung necrotizing pneumonia, pyothorax, abscess in the infraspinatus muscle, and multiloculated fluid collections in the left hip joint. After inserting a chest tube and administering urokinase for the pyothorax, a bronchopleural fistula was suspected. The fistula was identified based on clinical symptoms and computed tomography scan findings. If a bronchopleural fistula is present, thoracic lavage should not be performed as it may cause complications such as contralateral pneumonia due to reflux.
Subject(s)
Bronchial Fistula , Empyema, Pleural , Lemierre Syndrome , Pleural Diseases , Pneumonia , Female , Humans , Young Adult , Adult , Lemierre Syndrome/complications , Lemierre Syndrome/diagnosis , Bronchial Fistula/complications , Bronchial Fistula/diagnostic imaging , Pleural Diseases/complications , Pleural Diseases/diagnostic imaging , Empyema, Pleural/complications , Empyema, Pleural/diagnostic imagingABSTRACT
In a human immunodeficiency virus type 1 (HIV-1)-infected individual, immune-pressure-mediated positive selection operates to maintain the antigenic polymorphism on the gp120 third variable (V3) loop. Recently, we suggested on the basis of sequencing C2/V3 segments from an HIV-1 subtype E-infected family that a V3 sequence lineage group of the non-syncytium-inducing (NSI) variants (group 1) was relatively resistant to positive selection pressure (35). To better understand the relationship between the intensity of positive selection pressure and cell tropism of the virus, we determined the linkage between each V3 genotype and its function of directing coreceptor preference and MT2 cell tropism. The biological characterization of a panel of V3 recombinant viruses showed that all of the group 1 V3 sequences could confer an NSI/CCR5-using (NSI/R5) phenotype on HIV-1(LAI), whereas the group 2 V3 sequence, which was more positively charged than the group 1 sequence, dictated mainly a syncytium-inducing, CXCR4-using (SI/X4) phenotype. Phylogenetic analysis of C2/V3 sequences encoding group 1 or 2 V3 suggested that the variants carrying group 1 V3 are the ancestors of the intrafamilial infection and persisted in the family, while the variants carrying group 2 V3 evolved convergently from the group 1 V3 variants during disease progression in the individuals. Finally, a statistical test showed that the V3 sequence that could dictate an NSI/R5 phenotype had a synonymous substitution rate significantly higher than the nonsynonymous substitution rate. These data suggest that V3 sequences of the subtype E NSI/R5 variants are more resistant to positive selection pressure than those of the SI/X4 variants.
Subject(s)
Genetic Variation , HIV Envelope Protein gp120/genetics , HIV-1/genetics , Peptide Fragments/genetics , Receptors, CCR5/physiology , Selection, Genetic , Adult , Amino Acid Sequence , Base Sequence , Child , Evolution, Molecular , Female , Giant Cells/physiology , HIV-1/classification , HIV-1/physiology , Humans , Male , Molecular Sequence Data , Phenotype , Receptors, CCR5/genetics , Recombinant Proteins , Tumor Cells, Cultured , Virus ReplicationABSTRACT
It has been suggested that immune-pressure-mediated positive selection operates to maintain the antigenic polymorphism on the third variable (V3) loop of the gp120 of human immunodeficiency virus type 1 (HIV-1). Here we present evidence, on the basis of sequencing 147 independently cloned env C2/V3 segments from a single family (father, mother, and their child), that the intensity of positive selection is related to the V3 lineage. Phylogenetic analysis and amino acid comparison of env C2/V3 and gag p17/24 regions indicated that a single HIV-1 subtype E source had infected the family. The analyses of unique env C2/V3 clones revealed that two V3 lineage groups had evolved in the parents. Group 1 was maintained with low variation in all three family members regardless of the clinical state or the length of infection, whereas group 2 was only present in symptomatic individuals and was more positively charged and diverse than group 1. Only virus isolates carrying the group 2 V3 sequences infected and induced syncytia in MT2 cells, a transformed CD4(+)-T-cell line. A statistically significant excess of nonsynonymous substitutions versus synonymous substitutions was demonstrated only for the group 2 V3 region. The data suggest that HIV-1 variants, possessing the more homogeneous group 1 V3 element and exhibiting the non-syncytium-inducing phenotype, persist in infected individuals independent of clinical status and appear to be more resistant to positive selection pressure.
