Thrombocytopenia Associated With Teicoplanin Use: A Retrospective Observational Study.

BACKGROUND: Contradictory studies reporting vast heterogeneity in the teicoplanin-induced thrombocytopenia (TIT) incidence exist. OBJECTIVE: To identify the incidence of TIT associated with teicoplanin dosing range (6-12 mg/kg/dose) and the risk factors of TIT. METHODS: This retrospective observational study included adult patients who received teicoplanin for ≥3 consecutive days over a period of 3.5 years. Thrombocytopenia was defined as a platelet count of <100 × 103/µL coupled with at least a 25% drop from the baseline count. The TIT incidence was assessed using the adverse drug reaction probability scale (Naranjo scale). RESULTS: Data from 482 patients who received teicoplanin and met the predefined inclusion criteria were included in the analyses. The cohort presented a mean age of 53.5 ± 19 years, where 72.4% were male, and 49.2% exhibited normal baseline renal function. Teicoplanin was most commonly used for bacteremia (n = 134), and the most common isolated pathogen being Staphylococcus aureus (n = 221). The TIT incidence was 4.6% (the possible and probable category using the Naranjo scale; 22/482). The median time to first platelet count dropped to <100 × 103/µL after teicoplanin initiation was 5 (interquartile range [IQR], 3-10) days and 8 (IQR, 5-14) days till the maximum platelet count dropped. None of the tested patient variables were found to be independently associated with an increased risk of thrombocytopenia. CONCLUSION AND RELEVANCE: The overall TIT incidence was low across our study cohort, including critically ill patients. Our study results may aid in the optimal monitoring of such serious teicoplanin-induced adverse effects.

Genetic variation between Biomphalaria alexandrina snails susceptible and resistant to Schistosoma mansoni infection.

Much effort has been made to control schistosomiasis infection in Egypt. However, enduring effects from such strategies have not yet been achieved. In this study, we sought to determine the genetic variability related to the interaction between Biomphalaria alexandrina snails and Schistosoma mansoni. Using RAPD-PCR with eight (10 mers) random primers, we were able to determine the polymorphic markers that differed between snails susceptible and resistant to Schistosoma mansoni infection using five primers out of the eight. Our results suggest that the RAPD-PCR technique is an efficient means by which to compare genomes and to detect genetic variations between schistosomiasis intermediate hosts. The RAPD technique with the above-noted primers can identify genomic markers that are specifically related to the Biomphalaria alexandrina/Schistosoma mansoni relationship in the absence of specific nucleotide sequence information. This approach could be used in epidemiologic surveys to investigate genetic diversity among Biomphalaria alexandrina snails. The ability to determine resistant markers in Biomphalaria alexandrina snails could potentially lead to further studies that use refractory snails as agents to control the spread of schistosomiasis.

Biomphalaria species in Alexandria water channels.

Of the several species of Biomphalaria snails worldwide that serve as the intermediate host for Schistosoma mansoni, Biomphalaria alexandrina is a species that is indigenous to Egypt. Recently, there has been much debate concerning the presence of Biomphalaria glabrata and the hybrid of the species with Biomphalaria alexandrina. Due to this debate, the absence of a clear explanation for the presence of B. glabrata in Egyptian water channels and the probability that they may be reintroduced, we conducted this field study to identify Biomphalaria species present in Alexandria water channels. Laboratory-adapted susceptible snails to Schistosoma mansoni of the following species were used as a reference; Biomphalaria alexandrina, Biomphalaria glabrata and their hybrid. These snails were used to perpetuate the Schistosoma life cycle at the Theodor Bilharz Research Institute (TBRI), Cairo, Egypt. Morphological and molecular studies were conducted on these reference snails as well as on the first generation of Biomphalaria snails from two areas in the Alexandria governorate. The morphological study included both external shell morphology and internal anatomy of the renal ridge. The molecular study used a species-specific PCR technique. The results demonstrated that there was an absence of Biomphalaria glabrata and the hybrid from Alexandria water channels. Moreover, the susceptibility patterns of these reference snails were studied by measuring the different parasitological parameters. It was found that Biomphalaria glabrata and the hybrid were significantly more susceptible than Biomphalaria alexandrina to the Egyptian strain of Schistosoma mansoni. The results demonstrated that if Biomphalaria glabrata was reintroduced and adapted to the local environment in Egypt, it would have important epidemiologic impacts that would have a serious effect on the health of Egyptian people.