TABLE 1.

Summary of clinical findings for patients testing positive for HHV-6 by FA-ME panel

Patient	Genderf	Age (yrs)	Length of stay (days)	Previously healthyg	Presented symptomsi	CSFh results for:			Empirical antiviral treatment	Antiviral treatment after FA-ME	ciHHV-6 j present	HHV-6 genotype	Whole-blood HHV-6 qPCR value (no. of genomes/ml)	Positive laboratory finding(s) other than FA-MEk	Radiographic finding(s)l	ID consultm	Diagnosis
						WBCa (cells/mm3)	Glucose (mg/dl)	Protein (mg/dl)
1b	M	1.22	Expired	Yes	Fever, emesis, altered mental status	0.89	83	426	Acyclovir	Ganciclovir	No	B	3,371	None	Infarctions in the bilateral putamen and in the medial thalami; cerebral edema	Yes	HHV-6 meningoencephalitis
2	M	0.02	4.7	Yes	Fever, irritability	6	38	141	None	None	Not done	Not done	Not done	None	Not done	No	Presumptive primary HHV-6 infection
3	F	0.55	2.6	Yes	Fever, emesis, loose stool, episodic limpness	0	77	26	None	None	Not done	Not done	Not done	None	Not done	No	Presumptive primary HHV-6 infection
4	F	1.21	1.1	Yes	Fever, seizures, diarrhea	0	62	28	Acyclovir	None	No	B	33,174	Urine positive for Enterococcus faecalis	Unremarkable appearance of the brain	Yes	Presumptive primary HHV-6 infection
5	M	0.04	5.3	Yes	Fever, lethargy	5.996	35	98	Acyclovir	None	Not done	Not done	Not done	Urine positive for Klebsiella pneumoniae	Not done	No	Presumptive primary HHV-6 infection
6c	M	0.91	13.8	Yes	Fever, emesis, diarrhea, seizures	6,141	25	166	Acyclovir	None	Not done	Not done	Not done	None	Leptomeningeal enhancement, most prominent along the bilateral frontal and parietal regions	Yes	Presumptive primary HHV-6 infection
7	F	1.32	expired	No (brain neoplasm, on chemotherapy)	Brain neoplasm, hydrocephalus	0	Not done	Not done	None	None	Yes	B	89,844	Blood positive for Streptococcus mitis; urine positive for Proteus mirabilis;lower back drainage positive for Pseudomonas aeruginosa and E. faecalis	T2 hyperintense mass	Yes	Probable reactivation
8	F	6.01	11.4	Yes	Fever, headache	138.976	46	356	Acyclovir	Ganciclovir	No	B	<280	EBV DNA detected from CSF	Numerous multifocal areas of signal abnormality within the white matter	Yes	HHV-6 meningoencephalitis
9	F	17.01	7.6	Yes	Sensory loss, weakness, fever, abnormal gait, headache	843.99	45	101	Acyclovir	Ganciclovir, then oral valganciclovir	No	Not done	<280	None	Multiple nonenhancing scattered T2/FLAIR hyperintense foci within subcortical and deep white matter	Yes	Probable reactivation
10b	M	0.01	2.7	Yes	Rash	13	46	104	Acyclovir	None	No	B	508,427	Urine positive for Escherichia coli	Not done	Yes	Presumptive primary HHV-6 infection
11	F	0.43	1.3	Yes	Fever, irritability, bulging fontanelles	0.2	61	38	None	None	Not done	Not done	Not done	None	Small extra-axial fluid collections, probably developmental; no evidence of intracranial mass or hemorrhage	No	Probable HHV-6 meningoencephalitis/meningitis
12d	M	0.08	2.7	Yes	Fever, cough	947.7	40	81	None	None	No	Not done	Not done	None	Not done	No	Presumptive primary HHV-6 infection
13	M	0.07	7.6	Yes	Fever	2.962	37	56	Acyclovir	None	Not done	Not done	Not done	NP swab positive for rhinovirus/enterovirus	Not done	Yes	Presumptive primary HHV-6 infection
14	M	0.04	9.9	Yes	Fever, jaundice, congestion, cough	0	36	195	None	None	Yes	A	2,855,447	Blood positive for Streptococcus vestibularis; NP swab positive for RSV	Not done	Yes	Significance unknown
15	F	0.12	0.2	Yes	Fever, diarrhea	0	49	47	None	None	No	B	Not done	None	Not done	No	Presumptive primary HHV-6 infection
16	M	0.07	1.3	Yes	Fever	5.932	37	108	Acyclovir	None	Yes	B	2,346,517	None	Not done	No	Significance unknown
17	M	1.87	12.7	No (microcephaly)	Microcephaly, seizures, vomiting, constipation, fussy	0	60	32	None	None	No	B	Not done	None	Not done	No	Probable reactivation
18	M	12.87	1.3	Yes	Fever, stiff neck, vomiting, sensitivity to light	Not done	44	102	Acyclovir	None	No	Not done	Not done	None	Tiny focus of nonspecific T2/FLAIR hyperintensity in the left frontal white matter; no evidence of abnormalities	No	HHV-6 meningitis
19	M	0.54	0.8	Yes	Fever, bulging fontanelles	0	67	618	None	None	No	B	Not done	None	Not done	No	Probable HHV-6 meningoencephalitis/meningitis
20	M	0.54	0.1	Yes	Fever, fussiness, bulging fontanelles	0	58	32	None	None	No	Not done	Not done	None	No evidence of abnormalities other than mild prominence of the extra-axial spaces is noted without significant associated mass effect	No	Probable HHV-6 meningoencephalitis/meningitis
21b	M	12.59	25.8	No (HSCT)	HSCT, altered mental status, acute GVHD, hypertension, diarrhea, seizures	0	77	26	Cidofovir	Foscarnet	No	B	271,518	Adenovirus and EBV DNA detected from blood; NP swab positive for rhinovirus/enterovirus and adenovirus	Mild/moderately enlarged ventricles, with FLAIR hyperintensity; new areas of diffusion restriction seen suggesting an acute ischemic insult to the brain	Yes	HHV-6 meningoencephalitis
22	M	0.84	2.6	Yes	Fever, irritability, cough, rash	0.89	83	426	Acyclovir	Ganciclovir	No	B	296,494	None	Not done	Yes	Presumptive primary HHV-6 infection
23	M	0.15	3.8	Yes	Fever	1	115	93	None	None	No	B	Not done	Urine positive for E. faecalis	Not done	Yes	Presumptive primary HHV-6 infection
24	F	0.76	18.2	yes	Fever, emesis, altered mental status, seizure, left foot twitching	0	Not done	Not done	Acyclovir	Ganciclovir	No	B	2,549	CSF positive for HHV-6 by mNGS; stool positive for norovirus	Innumerable small, scattered foci of diffusion restriction with corresponding T2 hyperintensity	Yes	HHV-6 meningoencephalitis
25e	M	0.67	1.6	Yes	Fever, bulging fontanelles	2	63	25	None	None	Not done	Not done	Not done	None	Not done	No	Probable HHV-6 meningoencephalitis/meningitis

^aA ratio of 1:500 (WBC:RBC) was used to correct WBC values.

^bPatients were admitted to intensive care units.

^cCoinfection with HHV-6 and Streptococcus pneumoniae.

^dCoinfection with HHV-6 and enterovirus.

^eHHV-6 IgM negative.

^fM, male; F, female.

^gHSCT, hematopoietic stem cell transplant.

^hCSF, cerebrospinal fluid.

ⁱGVHD, graft versus host disease.

^jciHHV-6, chromosomally integrated HHV-6.

^kNP, nasopharyngeal; EBV, Epstein-Barr virus; RSV, respiratory syncytial virus; mNGS, metagenomic next-generation sequencing.

^lFLAIR, fluid-attenuated inversion recovery; T2, transverse relaxation time.

^mID, infectious disease.