Toxoplasma gondii - Revision history

Aidan at 20:40, 3 July 2025

2025-07-03T20:40:30Z

← Older revision		Revision as of 20:40, 3 July 2025
Line 19:		Line 19:
	*Seroprevalence around 10-18% in Canada [[CiteRef::shuhaiber2003se]][[CiteRef::ford-jones1996se]]		*Seroprevalence around 10-18% in Canada [[CiteRef::shuhaiber2003se]][[CiteRef::ford-jones1996se]]
	**As high as 60% in Nunavut, however [[CiteRef::messier2009se]]		**As high as 60% in Nunavut, however [[CiteRef::messier2009se]]
			*Global seroprevalence is around 30 to 40%[[CiteRef::bokaie2020se]]
	*There are large parts of South and Central America, as well as Pacific Islands, that have very high seroprevalence [[CiteRef::pappas2009to]]		*There are large parts of South and Central America, as well as Pacific Islands, that have very high seroprevalence [[CiteRef::pappas2009to]]

Aidan at 15:20, 17 October 2024

2024-10-17T15:20:33Z

← Older revision		Revision as of 15:20, 17 October 2024
Line 1:		Line 1:
		⚫	==Background==

	*Protozoan parasite associated with cats and raw beef mostly known for causing opportunistic infections and congenital infections		*Protozoan parasite associated with cats and raw beef mostly known for causing opportunistic infections and congenital infections

⚫	==Background==
	===Microbiology===		===Microbiology===

Aidan at 17:51, 19 September 2024

2024-09-19T17:51:06Z

← Older revision		Revision as of 17:51, 19 September 2024
Line 112:		Line 112:
	**[[Is treated by::TMP-SMX]]		**[[Is treated by::TMP-SMX]]
	***Dose unclear; 40-120 mg/kg/day or 5 mg/kg (TMP component) p.o./IV every 8 hours		***Dose unclear; 40-120 mg/kg/day or 5 mg/kg (TMP component) p.o./IV every 8 hours
			***Likely safer than and as effective as the pyramethamine-based regimens[[CiteRef::prosty2022re]]
	***Likely safer than and as effective as the pyramethamine-based regimens<ref>Prosty C, Hanula R, Levin Y, Bogoch II, McDonald EG, Lee TC. Revisiting the Evidence Base for Modern Day Practice of the Treatment of Toxoplasmic Encephalitis: A Systematic Review and Meta-Analysis. Clin Infect Dis. 2022 Aug 9:ciac645. doi: 10.1093/cid/ciac645. Epub ahead of print. PMID: 35944134.</ref>
	***Given these new data, in the context of the difficulty and expense of obtainined pyramethamine, TMP-SMX may be considered first-line		***Given these new data, in the context of the difficulty and expense of obtainined pyramethamine, TMP-SMX may be considered first-line
	**[[Is treated by::Atovaquone]] 1500 mg PO bid + [[pyrimethamine]]		**[[Is treated by::Atovaquone]] 1500 mg PO bid + [[pyrimethamine]]

Aidan: /* Management */ added new study re: TMP-SMX

2022-08-17T15:16:25Z

Management: added new study re: TMP-SMX

← Older revision		Revision as of 15:16, 17 August 2022
Line 100:		Line 100:
	==Management==		==Management==

			=== Toxoplasmosis Encephalitis ===
	*In general, in the setting of known HIV and one or more suspicious lesions, treat empirically for CNS toxoplasmosis and reassess with repeat imaging at around 10 days, at which time there should be some response		*In general, in the setting of known HIV and one or more suspicious lesions, treat empirically for CNS toxoplasmosis and reassess with repeat imaging at around 10 days, at which time there should be some response
	*First-line is a combination of [[Is treated by::pyrimethamine]] and [[Is treated by::sulfadiazine]]		*First-line is a combination of [[Is treated by::pyrimethamine]] and [[Is treated by::sulfadiazine]], though that may be changing (see TMP-SMX, below)
	**[[Is treated by::Pyrimethamine]] (with folinic acid) is the backbone		**[[Is treated by::Pyrimethamine]] (with folinic acid) is the backbone
	***[[Pyrimethamine]] 200 mg PO once followed by 50 mg PO daily if ≤60 kg or 75 mg PO daily if >60 kg		***[[Pyrimethamine]] 200 mg PO once followed by 50 mg PO daily if ≤60 kg or 75 mg PO daily if >60 kg
Line 110:		Line 111:
	*Alternatives		*Alternatives
	**[[Is treated by::TMP-SMX]]		**[[Is treated by::TMP-SMX]]
			***Dose unclear; 40-120 mg/kg/day or 5 mg/kg (TMP component) p.o./IV every 8 hours
			***Likely safer than and as effective as the pyramethamine-based regimens<ref>Prosty C, Hanula R, Levin Y, Bogoch II, McDonald EG, Lee TC. Revisiting the Evidence Base for Modern Day Practice of the Treatment of Toxoplasmic Encephalitis: A Systematic Review and Meta-Analysis. Clin Infect Dis. 2022 Aug 9:ciac645. doi: 10.1093/cid/ciac645. Epub ahead of print. PMID: 35944134.</ref>
			***Given these new data, in the context of the difficulty and expense of obtainined pyramethamine, TMP-SMX may be considered first-line
	**[[Is treated by::Atovaquone]] 1500 mg PO bid + [[pyrimethamine]]		**[[Is treated by::Atovaquone]] 1500 mg PO bid + [[pyrimethamine]]
	**[[Atovaquone]] 1500 mg PO bid ± [[sulfadiazine]]		**[[Atovaquone]] 1500 mg PO bid ± [[sulfadiazine]]
	**[[Azithromycin]] 900-1200 mg PO daily + [[pyrimethamine]]		**[[Azithromycin]] 900-1200 mg PO daily + [[pyrimethamine]]

	===HIV===		==== Patients with HIV ====

	*[[Is treated by::Pyrimethamine]] 200 mg PO once, followed by dose based on body weight:		*[[Is treated by::Pyrimethamine]] 200 mg PO once, followed by dose based on body weight:
	**Body weight ≤60 kg: [[Is treated by::pyrimethamine]] 50 mg PO daily + [[Is treated by::sulfadiazine]] 1000 mg PO q6h + leucovorin 10–25 mg PO daily (can increase to 50 mg daily or BID)		**Body weight ≤60 kg: [[Is treated by::pyrimethamine]] 50 mg PO daily + [[Is treated by::sulfadiazine]] 1000 mg PO q6h + leucovorin 10–25 mg PO daily (can increase to 50 mg daily or BID)

Aidan: /* Pregnancy */

2020-09-15T12:31:37Z

Pregnancy

← Older revision		Revision as of 12:31, 15 September 2020
Line 60:		Line 60:

	*As with other immunocompetent people, it is largely asymptomatic		*As with other immunocompetent people, it is largely asymptomatic
			*Refer to [[Toxoplasmosis in pregnancy]]
	*Only half of women can identify a significant risk factor [[CiteRef::boyer2011un]]
	*Risk of transmission to fetus is with parasitemia associated with primary infection, so women who are seropositive are ''not'' at risk of having a child with congenital infection

	===Congenital===		===Congenital===
Line 96:		Line 95:

	*Not routinely done		*Not routinely done
	*May be helpful from CSF or vitreous humour		*May be helpful from CSF, vitreous humour, or amniotic fluid
	*Not helpful on brain biopsy tissue		*Not helpful on brain biopsy tissue

Line 129:		Line 128:
	===Pregnancy===		===Pregnancy===

			*Refer to [[Toxoplasmosis in pregnancy#Management\|Toxoplasmosis in pregnancy]]
	*To treat active disease in mother:
	**[[Is treated by::Pyrimethamine]] is relatively contraindicated in pregnancy as it is toxic before 14 weeks gestation
	**If life-threatening, should likely need treatment and consider abortion (if early in pregnancy)
	*To prevent congenital toxoplasmosis:
	**[[Is treated by::Spiromycin]] 1 g q8h is safe throughout pregnancy, and decreases transmission to fetus, but is not enough to treat CNS disease
	**After fetal infection is confirmed around 18 weeks, [[pyrimethamine]] 50 mg bid for 2 days then 50 mg daily, plus [[sulfadiazine]] 75 mg/kg/d split bid for 2 days then 50 mg/kg bid, plus [[leucovorin]] 10-20 mg daily

	==Prevention==		==Prevention==

Aidan: /* Serology */

2020-09-15T12:14:56Z

Serology

← Older revision		Revision as of 12:14, 15 September 2020
Line 77:		Line 77:
	===Serology===		===Serology===

			*Serology is the mainstay of diagnosis[[CiteRef::gangneux2012ep]]
	*ELISA IgG for prior exposure; ELISA IgM for acute infection
			*IgM antibodies
	*~~IgM~~ titres plateau within 1 month, and ~~IgG~~ ~~within~~ ~~2-3~~ months		**Detectable within 1 week, and titres plateau within 1 month and start decreasing after 1 to 6 months
	*IgM is still detectable for months or years after infection
	*IgM ~~avidity~~ ~~testing~~ ~~can~~ ~~help~~ to ~~assess~~ ~~how~~ ~~recently the~~ infection ~~was acquired~~		**IgM is still detectable for months or years after infection
			***Rarely, lost within 3 months
			***25% lost within 7 months
			***Often detectable for more than a year
			*IgG antibodies
			**Detectable 2 to 4 weeks after infection, and plateaus within 2 to 3 months
			**Declines but persists lifelong
			*IgG avidity testing can help to assess how recently the infection was acquired
	**Provides a measure of how tightly the antibodies bind, which is highest in early infection		**Provides a measure of how tightly the antibodies bind, which is highest in early infection
	**A high avidity ratio (weak binding) suggests that the infection was acquired at least 4 months prior		**A high avidity ratio (weak binding) suggests that the infection was acquired at least 4 months prior
			**Treatment delays avidity
			**Most useful during the first trimester of pregnancy, when high avidity effectively rules out acquisition during pregnancy

	===PCR===		===PCR===

Aidan: /* Management */

2020-08-28T22:18:54Z

Management

Show changes

Aidan: Text replacement - "([Ss])olid-organ" to "$1olid organ"

2020-08-07T13:52:38Z

Text replacement - "([Ss])olid-organ" to "$1olid organ"

← Older revision		Revision as of 13:52, 7 August 2020
Line 10:		Line 10:
	* Modes of transmission		* Modes of transmission
	** Ingesting tissue cysts in meat, or oocytes in food or water		** Ingesting tissue cysts in meat, or oocytes in food or water
	** Solid-organ transplantation, especially heart		** Solid organ transplantation, especially heart
	** Vertical or transplacental transmission		** Vertical or transplacental transmission
	** Case reports of lab-acquired needlestick transmission		** Case reports of lab-acquired needlestick transmission

Aidan: Text replacement - "== Clinical Presentation" to "== Clinical Manifestations"

2020-08-02T10:51:30Z

Text replacement - "== Clinical Presentation" to "== Clinical Manifestations"

← Older revision		Revision as of 10:51, 2 August 2020
Line 33:		Line 33:
	* Infection triggers a Th-1 response		* Infection triggers a Th-1 response

	== Clinical ~~Presentation~~ ==		== Clinical Manifestations ==
	=== Immunocompetent ===		=== Immunocompetent ===
	* Asymptomatic in 80% of primary infections		* Asymptomatic in 80% of primary infections

Aidan: changed headings

2020-02-09T01:12:47Z

changed headings

Show changes