Atraumatic splenic rupture from Babesia: A disease of the otherwise healthy patient.

Babesiosis, an infection caused by the protozoan Babesia microti and transmitted by the Ixodes scapularis tick, is commonly described in the literature with an approximate incidence of 1000 cases per year (Herwaldt et al., 2012). Infections in North America occur most frequently during the spring and summer months in the Northeastern and Midwestern United States. Babesia can cause a wide spectrum of clinical manifestations ranging from a self-limited febrile illness or mild anemia to severe illness causing acute respiratory distress syndrome (ARDS), disseminated intravascular coagulopathy (DIC) and multisystem organ failure. Severe illness most commonly occurs in elderly, immunocompromised, or asplenic patients (Vannier and Krause, 2012). Splenic rupture has been generally described as a complication of severe illness secondary to babesiosis. We describe a case of spontaneous splenic rupture in an otherwise healthy woman that required emergent splenectomy. Recent case reports suggest that splenic rupture occurs in people without known risk factors for severe babesiosis. Physicians should be aware of this acute presentation in otherwise healthy individuals.

Rapid detection of convallatoxin using five digoxin immunoassays.

CONTEXT: Cardiac glycosides of plant origin are implicated in toxic ingestions that may result in hospitalization and are potentially lethal. The utility of commonly available digoxin serum assays for detecting foxglove and oleander ingestion has been demonstrated, but no studies have evaluated the structurally similar convallatoxin found in Convallaria majalis (lily of the valley) for rapid laboratory screening, nor has digoxin immune Fab been tested as an antidote for this ingestion. OBJECTIVE: We aimed to (1) evaluate multiple digoxin assays for cross-reactivity to convallatoxin, (2) identify whether convallatoxin could be detected in vivo at clinically significant doses, and (3) determine whether digoxin immune Fab could be an effective antidote to convallatoxin. MATERIALS AND METHODS: Cross-reactivities of purified convallatoxin and oleandrin with five common digoxin immunoassays were determined. Serum from mice challenged with convallatoxin was tested for apparent digoxin levels. Binding of convallatoxin to digoxin immune Fab was determined in vitro. RESULTS: Both convallatoxin and oleandrin were detectable by a panel of commonly used digoxin immunoassays, but cross-reactivity was variable between individual assays. We observed measurable apparent digoxin levels in serum of convallatoxin intoxicated mice at sublethal doses. Convallatoxin demonstrated no binding by digoxin immune Fab. CONCLUSION: Multiple digoxin immunoassays detect botanical cardiac glycosides including convallatoxin and thus may be useful for rapid determination of severe exposures, but neutralization of convallatoxin by digoxin immune Fab is unlikely to provide therapeutic benefit.

Comparative peptide mapping of a hepatitis C viral recombinant protein by capillary electrophoresis and matrix-assisted laser desorption time-of-flight mass spectrometry.

Capillary electrophoresis (CE) and matrix assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF-MS) were investigated as alternatives to sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis for peptide mapping with Staphylococcus aureus protease (V8) of a hydrophobic recombinant hepatitis C virus antigen, HC-31, which required 0.1% SDS for solubility. Controls (V8 only) or HC-31 digests were extracted with chloroform-methanol-water (1:4:3) to remove SDS, which interferes with MALDI-TOF, and high salt content, which affects CE. In two different runs by CE, the elution times of each of 11 peptide peaks were very reproducible (R.S.D. < 0.016). 25 fragments were resolved by MALDI-TOF-MS, including six smaller peptides (M(r) < 13 000) resulting from V8 autodigestion. MALDI-TOF-MS indicated that partial cleavages occurred, primarily at sites where there are paired glutamic and/or aspartic acid residues.