Table 1 Data for 13 positive slides (above horizontal line) and for 21 slides with discordant results (below line).
From: Performance of a malaria microscopy image analysis slide reading device
Slide # | WHT Result | WHT P/ul | RDT result | # reads agree | RR Dx | median if pos | # discordant reads | Alt Dx | Reference Reader COMMENTS |
|---|---|---|---|---|---|---|---|---|---|
63 | pf | 100 | PF | 5 | pf | 47 | 1 | NEG | Thick not stained completely; Thin film: incorrectly fixed |
143 | pf | 10,000 | PF | 7 | pf | 160 | 0 | microfilariae present; Staining was blue color. | |
137 | pf | 1,500 | PF | 7 | pf | 596 | 0 | Not good staining, much detritus at edge thick smear. | |
72 | pf | 1,600 | PF | 6 | pf | 652 | 0 | Thin film incorrectly fixed | |
61 | pf | 2,800 | PF | 6 | pf | 673 | 0 | no comments | |
56 | Pf/pm | 800 | MIX | 6 | pf | 675 | 0 | 10% ring forms; Plasmodium falciparum | |
118 | pf | 571 | PF | 6 | pf | 724 | 0 | gametocytes (some rounded up); Thin smear: too thick + fixation inadequate | |
44 | pf | 100 | PF | 6 | pf | 1,151 | 0 | Malaria pigment seen. Parasites not well stained. Thick film not well distributed. massive stain deposit and presence of multiple artifacts | |
68 | Pf/pm | 8,000 | MIX | 6 | pf | 1,916 | 0 | Thick film: not completely stained; Thin film: incorrectly fixed | |
115 | Pf/pm | 31,600 | MIX | 6 | pf | 34,811 | 0 | beautiful parasites! Slide with crack! Thick smear: irregular distribution; Thin smear: too thick | |
117 | Pf/pm | 17,200 | MIX | 6 | pf | 54,613 | 0 | beautiful parasites! thin smear: too thick | |
78 | pf | 50 | PF | 4 | pf | 207 | 2 | pfpo | A difficult but interesting slide. It is obviously a mixed infection of P. falciparum and either |
P. vivax or P. ovale. Some parasites in the thick film have a pinkish background that I associate with P. ovale. Parasitized rbcs in the thin film lack obvious stippling and are normal in size or only very slightly enlarged. About half of the parasitized rbcs in the thin film are distorted in shape (oblong) and/or have fimbriae that is characteristic of P. ovale. This slide is designed to drive readers crazy. There are many large trophs in the thick film with a pinkish "fried egg" appearance, typical in my experience of P. ovale. There are rings with could be either ovale or falciparum. In the thick film I saw one beautiful P.f. gametocyte (confirming P falciparum) and several large, ameboid trophs in rbc's that were only slightly enlarged. This is obviously a mixed infection of falciparum and, most likely, ovale. | |||||||||
74 | Pf/ pm | 150 | MIX | 3 | pv | 110 | 4 | po | A difficult slide for me. It is obviously either P. vivax or P. ovale. The parasites in the thin film lack |
obvious stippling and are either normal in size or only very slightly enlarged. About 50% of them however had a distorted "oblong" shape and/or fimbriae that is characteristic of P. ovale. I have called this PO because of the compactness of the trophs and stippling on the thick film but the staining on the thin film does not show the stippling or good morphology; thick film: with air bubble; pigment in WBC | |||||||||
111 | NEG | NEG | 4 | NEG | 2 | pf | Thick smear: irregular distribution hemolysation: staining inadequate; fixation inadequate | ||
131 | NEG | NEG | 4 | NEG | 2 | pf | contaminated with bacteria; many eosiniphils; Thin smear: too thick and grease on the slide | ||
134 | NEG | NEG | 4 | NEG | 2 | pf | Thick smear: irregular distribution; Filaria: Manzonella perstans | ||
135 | NEG | NEG | 4 | NEG | 2 | pf | Thick smear: irregular distribution Filaria: Manzonella perstans; | ||
130 | NEG | NEG | 4 | NEG | 2 | pf | Thick smear: distribution irregularFilaria! Manzonella perstans; grease on the slide | ||
129 | NEG | NEG | 4 | NEG | 2 | pf | Microfilariae of Mansonella perstans; Eosinophils ++thick smear: contaminated (bacteria + dust) | ||
147 | pf | 3,000 | OTRO PLAS | 4 | NEG | 3 | pf | algal contamination of stain | |
144 | NEG | NEG | 5 | NEG | 2 | pf | not a good slide - too much precipitate; Two destroyed gamete. Too much precipitate, debris; Fixed edges | ||
133 | NEG | NEG | 4 | NEG | 2 | pf | Thick film: irregular distribution; thin film: too thin | ||
132 | NEG | MIX | 4 | NEG | 2 | pf | Thick smear: contaminated with bacteria and dust; Irregular distribution many eosinophils | ||
128 | NEG | NEG | 4 | NEG | 2 | pf | thick smear: contaminated (bacteria + dust); Thin smear: too thick | ||
116 | NEG | NEG | 4 | NEG | 2 | pf | thin smear: too thick + fixation inadequate | ||
140 | NEG | NEG | 5 | pf | 26 | 2 | NEG | Not good distribution of WBC in thick smear. | |
58 | NEG | NEG | 4 | pf | 30 | 2 | NEG | good staining. Pf; prob neg but bc artifacts and stain deposit single parasites in thick film can’t be ruled out | |
126 | NEG | NEG | 3 | pf | 35 | 3 | NEG | Thick smear: some contamination (dust)thin smear: too thick | |
136 | NEG | NEG | 3 | pf | 39 | 3 | NEG | Thick smear: irregular distribution contaminated with dust; thin smear: too thick | |
104 | NEG | NEG | 3 | pf | 74 | 3 | NEG | no comments | |
103 | NEG | PF | 4 | pf | 83 | 2 | NEG | 1x M. perstans microfilaria | |
43 | NEG | NEG | 3 | pf | 95 | 3 | NEG | Many dots could be confused as chromatin but were two sizes (big and smaller). Call pf pos but many artifacts | |
145 | pf | 1,000 | PF | 5 | pf | 111 | 2 | NEG | RINGS |
142 | pf | 5,000 | PF | 5 | pf | 160 | 2 | NEG | Algae present yeasts resemble Pfg |