Sensitivity and specificity of PCR on blood for diagnosis of HAT.

<p>Note. CI = confidence interval.</p

Classification of study participants according to reference standards for diagnosis, staging and follow-up (FU).

<p>At each follow-up time point, the number of patients attending is given. Patient groups reaching a final outcome of treatment failure during follow-up and excluded from analysis at subsequent time points, are indicated with an arrow.</p

Specificity and sensitivity of PCR on CSF during post-treatment follow-up.

<p>Note. CI = confidence interval.</p

A five month follow up of an efficacy study for a <i>T. evansi</i> experimentally infected goat model, using the haematocrit centrifugation technique (HCT), after treatment with Diminazene, DB 75, DB 867 or DB 1192 at various compound doses.

<p>The results are depicted as negative (−) or positive (+) for motile trypanosomes observed in goat blood samples, along with goats, which died (<i>D</i>) or were removed from the project (<i>Rem</i>) during the study period.</p

A five month follow up of an efficacy study for a <i>T. evansi</i> experimentally infected goat model, using the polymerase chain reaction (PCR), after treatment with Diminazene, DB 75, DB 867 or DB 1192 at various compound doses.

<p>The results are depicted as negative (−) or positive (+) for the presence of parasite DNA in goat blood samples, along with goats, which died (<i>D</i>) or were removed from the project (<i>Rem</i>) during the study period.</p

A five month follow up of an efficacy study for a <i>T. evansi</i> experimentally infected goat model, using a card agglutination test (CATT/<i>T. evansi</i>), after treatment with Diminazene, DB 75, DB 867 or DB 1192 at various compound doses.

<p>Results are depicted as strongly positive (+++), intermediate (++), weak (+) or negative (−) for agglutination, when goat plasma was mixed with an antigenic reagent, along with goats, which died (<i>D</i>) or were removed from the project (<i>Rem</i>) during the study period.</p

Plasma profiles obtained for the standard drug and test compounds used in a <i>T. evansi</i> experimental goat model of infection.

<p>Drug plasma concentrations of a) diminazene at 5 mg/kg (purple), b) DB 1192 at 2.5 mg/kg (orange) and 1.25 mg/kg (green), c) DB 75 at 2.5 mg/kg (orange) and 1.25 mg/kg (green) and d) DB 867 at 2.5 mg/kg (orange) and 1.25 mg/kg (green) are depicted. Horizontal red line shows ten-times the IC₅₀ for that respective compound.</p

Pharmacokinetic parameters determined for a treatment schedule of four applications of diminazene (at 5 mg/kg), DB 75, DB 867 and DB 1192 (at 2.5 mg/kg and 1.25 mg/kg), based on average plasma concentration levels taken from <i>T. evansi</i> experimentally infected goats.

<p>Pharmacokinetic parameters determined for a treatment schedule of four applications of diminazene (at 5 mg/kg), DB 75, DB 867 and DB 1192 (at 2.5 mg/kg and 1.25 mg/kg), based on average plasma concentration levels taken from <i>T. evansi</i> experimentally infected goats.</p

Signs of acute toxicity investigated after the i.m. application of DB 75, DB 867 and DB 1192 in a multiple compound application (4×1 mg/kg) toxicity trial.

<p>The presence or absence of each sign is depicted as a (✓) or as a (x), respectively.</p><p>*<b>Signs of acute toxicity:</b> Hypo: <i>Hypotension</i>; Hyper: <i>Hypertension</i>; (L): <i>Lacrimation</i>; (S): <i>Salivation</i> (excess); (Tr): <i>Tremors</i>; (Ir): <i>Irritation</i>; (U): <i>Urination</i> (excess); (D): <i>Diarrhoea</i>.</p

Performance of Parasitological and Molecular Techniques for the Diagnosis and Surveillance of <i>Gambiense</i> Sleeping Sickness

<div><p>Objectives</p><p>Recently, improvements have been made to diagnostics for <i>gambiense</i> sleeping sickness control but their performance remains poorly documented and may depend on specimen processing prior to examination. In a prospective study in the Democratic Republic of the Congo, we compared the diagnostic performance of several parasite detection techniques, immune trypanolysis and of m18S PCR on whole blood stored in a stabilisation buffer or dried on filter paper.</p><p>Methods</p><p>Individuals with CATT whole blood (WB) titer ≥1∶4 or with clinical signs indicative for sleeping sickness were examined for presence of trypanosomes in lymph node aspirate (LNA) and/or in blood. Blood was examined with Capillary Centrifugation Technique (CTC), mini-Anion Exchange Centrifugation Technique (mAECT) and mAECT on buffy coat (BC). PCR was performed on whole blood (i) stored in guanidine hydrochloride EDTA (GE) stabilisation buffer and (ii) dried on filter paper, and repeatability and reproducibility were assessed. Immune trypanolysis (TL) was performed on plasma.</p><p>Results</p><p>A total of 237 persons were included. Among 143 parasitologically confirmed cases, 85.3% had a CATT-WB titre of ≥1/8, 39.2% were positive in LNA, 47.5% in CTC, 80.4% in mAECT-WB, 90.9% in mAECT-BC, 95.1% in TL and up to 89.5% in PCR on GE-stabilised blood. PCR on GE-stabilised blood showed highest repeatability (87.8%) and inter-laboratory reproducibility (86.9%). Of the 94 non-confirmed suspects, respectively 39.4% and 23.4% were TL or PCR positive. Suboptimal specificity of PCR and TL was also suggested by latent class analysis.</p><p>Conclusion</p><p>The combination of LNA examination with mAECT-BC offered excellent diagnostic sensitivity. For PCR, storage of blood in stabilisation buffer is to be preferred over filter paper. TL as well as PCR are useful for remote diagnosis but are not more sensitive than mAECT-BC. For TL and PCR, the specificity, and thus usefulness for management of non-confirmed suspects remain to be determined.</p></div