Welcome back to our first case of the month, with a special case from Idzi Potters and the Institute of Tropical Medicine, Antwerp.  The following structures were found in a bronchoalveolar lavage from a middle-aged Belgian patient with asthma who presented with increased shortness of breath. He reports no travel out-of-country and works as an administrator at an insurance company. He recently reported an insect infestation in his home.Video credits are for Monique Vatlet (CHU Ambroise Paré, Mons, Belgium). Identification ..read more

 Answer to the Parasite Case of the Week 717: Brugia malayi This case was a little bit tricky in that the tail didn't show a clear terminal and subterminal nucleus as expected for B. malayi. However, the tail nuclei were separated, there is a long head space, and the sheath stained deep pink with Giemsa (the latter being a 'soft' feature).  To confirm the findings, many of you rightly noted that you would try to get the patient's travel history and also look for other microfilariae in this specimen. B. malayi is restricted to Asia and SE Asia and is a cause of lymphatic filariasis ..read more

 This week's classic case was generously provided by Florida Fan. The following was seen in a Giemsa-stained peripheral blood smear. No additional history is available. Diagnosis? Each division on the ruler is 2.5 micrometers; the object is slightly less than 250 micrometers long.  ..read more

 Answer to the Parasite Case of the Week 716: Cyclospora cayetanensis oocysts On the wet mount preparation with Lugol's iodine, one can nicely appreciate the spherical oocyst with well-defined outer wall and internal globular bodies. The oocysts are not highlighted by the Heine and trichrome stains (latter not shown), but their presence may be suspected by their negative contour. Confirmation can be made by staining with modified acid fast stain (or modified safranin stain), and by demonstrating autofluorescence with fluorescence microscopy.  It is important to measure the oocysts o ..read more

 Answer to the Parasite Case of the Week 715: Cockroach ootheca (egg case or 'purse') These fascinating structures contain about 30-40 eggs each. The female cockroach carries her ootheca until the eggs hatch and the first instar nymphs emerge. For those of you who had never heard of this phenomenon before, you can read more HERE.  In this case, we can see the emerging nymphs: Laura noted that the ootheca was hard and solid when it first arrived in the lab so she added some saline and waited for 30 minutes. This is when the nymphs began to poke out and she was able to remove them for ..read more

This week's interesting case was donated by Dr Mike Mitchell and his fantastic parasitology experts, Laura Derderian, Gwen Kee, and Brie Ray. The specimen below was submitted to the laboratory for evaluation of a possible parasite after being found in a 19 month girl's diaper. Identification? What is the significance to the patient ..read more

 Answer to the Parasite Case of the Week 714: Taenia species proglottid. Examination of the uterine branching pattern is required for species level identification when using morphology alone. Gravid proglottids (which we know we have here since we see eggs) can be categorized into 2 groups: Taenia solium proglottids have 7-13 primary lateral branches off of the central stem, whereas T. saginata and T. asiatica have 12-30. Of the three species, only T. solium causes human cysticercosis, so it is helpful to identify when T. solium is present. Options for determining the species of gravid pr ..read more

This week's case was donated by Dr. Sandeep T. You may remember the amazing case of fasciolopiasis he provided back in 2012 (and if not, you should definitely check it out HERE). His latest case from a middle aged taxi driver who reports passing white objects in is his stool for the past 2 years. He denies fever, weight loss, vomiting and diarrhea. A routine complete count is unremarkable with no anemia. Below is one of the white objects submitted for pathologic examination. Identification? What additional procedures would be helpful in this case ..read more

 Answer to the Parasite Case of the Week 713: Trichomonas vaginalis trophozoite As noted by Florida Fan, the Giemsa-stained preparation is ideal for highlighting the key morphologic features of T. vaginalis trophozoites, including the flagella, undulating membrane, and axostyle. In my mind, the Pap stain just doesn't highlight the features as well. Here is an annotated image showing some of these features: The trophozoites of T. vaginalis are 7-30 micrometers long, are tear drop/pear-shaped (i.e., pyriform), and have 5 flagella. Four flagella are anteriorly directed, while the 5th flagel ..read more

 Here is combination case from my archives showing a particular parasite in 3 different preparations of vaginal secretions. Conventional Pap smear: ThinPrep Pap smear: Giemsa-stained cytoprep: Identification ..read more