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Severe Toxoplasmosis Causing Respiratory Failure in an Immunocompetent Patient

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We describe a patient with toxoplasmosis presenting as severe community acquired pneumonia (CAP), progressive respiratory failure, hepatitis, hyperferritinemia, significant elevation of inflammatory markers, myositis, lymphopenia, LDH elevation and macrophage activation syndrome (MAS)-like picture requiring intubation, in a young immunocompetent female. The source of Toxoplasma gondii was infected venison procured by a hunter in the southern United States. The initial diagnosis of disseminated toxoplasmosis was made by metagenomics cell fee DNA in plasma. The diagnosis was further confirmed by Toxoplasma serologies, positive Toxoplasma PCR in bronchoalveolar lavage fluid, blood and liver biopsy and the histopathology of identifying the pathogen in a liver biopsy specimen . The astute clinician should be aware that severe toxoplasmosis should be part of the differential diagnosis of severe CAP, even in immunocompetent patients. This is particularly pertinent to patients who have significant exposures to wild game meat and other more common CAP-causing pathogens have been excluded. In this setting, the use of metagenomics cell free DNA can exclude a wide variety of pathogens and lead to early diagnosis and treatment. In patients with severe toxoplasmosis, empiric treatment with trimethoprim/sulfamethoxazole, until first line anti-Toxoplasma treatment with pyrimethamine/sulfadiazine/folinic acid becomes available, can be life-saving.

David ruttenberg and i’m a second year infectious disease fellow at the university of south florida and i’d like to discuss a case of severe toxoplasmosis that caused respiratory failure leading to intubation in an immunocompetent patient to give some background toxoplasma is an intracellular protozoan and it’s a major opportunistic infection that infects most of

The world’s population about one-third the definitive host for toxoplasma is felines and it can be transmitted through several routes including ingestion of the tissue cysts from raw or undercooked meat of an infected animal or if the soil contaminates food infection with toxoplasma and immunocompetent patients is usually nondescript and can often be confused

With other infections because of the similar resemblance other infections that can be similar to include influenza ebv cmv and hhv-6 severe or disseminated toxoplasma is best described in immunocompromised patients due to the reactivation of latent infection and this can lead to severe pneumonias brain abscesses or other types of infections our case revolves

Around a 32 year old very healthy female who came to our hospital with fevers of up to 103.5 fahrenheit sore throat cough biologists nausea vomiting and diarrhea for 10 days prior to presentation exam she was febrile of up to 102.9 and very hypoxic with a pulse oximetry reading of 85 percent on room air she was given supplemental oxygen via nasal cannula her

Lung exam was remarkable for faint by basil or crackles on her labs her white blood cells showed 11.7 her renal function was normal and she had elevated liver enzymes with an ast of 252 alt of 386 and she also had elevated inflammatory markers including crp and ferritin a respiratory vital viral panel and hiv antigen antibody tests were negative a cat scan of

The chest showed by basilar dependent consolidation of peribronchial nodularity and this could be seen in figure one in the center of the slide she was started on empiric ceftraxone for typical community acquired pneumonia but she was not improving further information was obtained from the patient’s friend on hospital day five and she revealed that the patient

Ate venison sausage that her husband procured from a hunting trip in alabama because of this her antibiotics were brought into vancomycin piper’s taseobactam and doxycycline evaluation for atypical infections such as toxoplasma were underway after serum toxoplasma igm igg and qualitative pcr were positive trimethoprim sulfamethoxazole 320 milligrams every 8 hours

Iv was added for very high suspicion of severe disseminated toxoplasmosis unfortunately she was intubated two days later for worsening respiratory failure further workup for toxoplasma include a bronchoscopic alveolar lavage which showed very high levels of toxoplasma dna metagenomic cell free dna was also sent to karius incorporated and that showed very high

Titers of toxoplasma as well confirmatory antibody testing at the remington specialty diagnostic laboratory was positive due to the elevated liver enzymes a liver biopsy was obtained and this showed tachyzoids on immunohistochemical stain that could be seen in figure 2a and clusters of epithelial histiocytes shown in figure 2b and these are both diagnostic for

Toxoplasma deer meat was obtained from the patient’s freezer and the liver biopsy tissue block was sent to the remington lab and both of these confirm toxoplasma by pcr on hospital day 9 the patient was extubated and she remained on trimethoprim sulfamethoxazole throughout the admission she was able to be weaned from oxygen and discharged home and she is still

Currently doing very well we believe that this is the first case of disseminated toxoplasmosis in an immunocompetent patient that caused severe pneumonia requiring intubation after the ingestion of venison in the united states toxoplasma as stated before is well known to cause severe disease in the immunocompromised population such as those with hiv recipients of

Solid or hematologic organ transplants or taking immunocompromised medications outbreaks of toxoplasma have been reported united states in the immunocompetent patients after the ingestion of venison but these only cause self-limiting mild disease and not severe disease requiring intubation like our patient additionally the causative organism for most pneumonias

Is identified in only 38 of patients since toxoplasmosis is considered a rare cause of pneumonia in immunocompetent hosts we don’t routinely check for it this means that the real incidence of toxoplasma causing communal acquired pneumonia is not known our case suggests that chromium acquired pneumonia due to toxoplasma could be more prevalent than we initially

Believe in french guiana outbreaks of toxoplasma severe toxoplasma have occurred after the ingestion of venison and there were other sporadic outbreaks near the amazon rainforest such as brazil colombia and peru these amazonian cases have not been reported in north america but our case showed surprising similarities in clinical presentation to toxoplasmosis cases

Near amazon infection with toxoplasma can be confirmed with serologic testing of pcr from the blood or other bodily fluids and immunohistochemistry from tissue biopsy or cytology the test for metagenomic sequencing panel is under clinical investigation for immunocompromised population but this was able to assist us in confirming a diagnosis and antibody testing

With igm and igg can be unreliable with commercial testing and should be done at a reference laboratory to conclude toxoplasma is an opportunistic parasite and causes one of the most uncommon infections in the world and it’s best known to cause severe disease and immunocompromise and only mild self-limiting diseases immunocompetent aside from our patient no cases

Of severe toxoplasmosis immunocompetent patients have been reported in the united states after the consumption of venison in south america around the amazon river severe toxoplasma similar to our patient has been reported we’re currently pending genetic sequencing of our identified strain of toxoplasma to determine if this could be the amazonian strain that migrated

To the united states we recommend that clinicians have a high index of suspicion when the etiology of community acquired pneumonia is unclear and it’s not responding to conventional antibiotic therapy testing through pcr biopsy and cell free metagenomics dna can quickly aid in a diagnosis and treatment for the patient and if the suspicion for toxoplasma is high

It can be empirically treated with high dose trimethoprim sulfamethoxazole until first line anti-toxic plasma treatment with pyrimethamine sulfadiazine and fluidic acid becomes available thank you so much for taking the time to listen to my talk

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Severe Toxoplasmosis Causing Respiratory Failure in an Immunocompetent Patient By David Rutenberg