Acanthamoeba Keratitis in Egypt: Characteristics and Treatment Outcomes

Figures & data

Figure 1 Ocular findings at presentation: Ring infiltrates ((A), 20 eyes), perineural infiltrates ((B), 29 eyes), hypopyon ((C), 7 eyes), scleritis ((D), 3 eyes), diffuse stromal infiltrates ((E), 26 eyes). After amniotic membrane grafting (F).

Table 1 Results of Diagnostic Tools in Both Groups: In Group A (Early Presenters), There Was No Significant Difference Between Different Methods to Diagnose Positive Cases. However, in Group B (Late Presenters), Culture Was Significantly More Accurate in Diagnosing AK

Positive Cases Diagnosed	Culture	Smear	IVCM
				X^2	p
Group A (n=24)	9 (37.5%)	12 (50%)	14 (58.3%)	2.347	0.309
Group B (n=20)	9 (45%)	4 (20%)	3 (15%)	4.292	0.038*
	0.831	0.021*	0.033*

Note: Asterisk (*) indicates statistical significance.

Table 2 Correlation Between CL Wear and Treatment Duration: A Significant Negative Correlation Was Found

		Treatment Duration (Days)
		Range	Mean ± SD	t-Test	p-value
CLs	+ ve	32–106	65.76 ± 22.34	10.721	0.002*
	-ve	55–130	88.07 ± 19.45

Note: Asterisk (*) indicates statistical significance.

Figure 2 Correlation between symptom to duration (STD) and duration of treatment: A statistically significant positive correlation was found (r=0.753, p=0.001) with linear trendline shown.

Figure 3 Uncorrected distance visual acuity: at presentation, and after treatment.

Table 3 Risk Factors and Clinical Features of AK in Previous Studies

	Africa	Europe	North America				Asia				Oceana
	Tanta (Our’s)	Bacon^Citation24	Hargrave^Citation25	Tu^Citation26	Chew^Citation27	Kaiserman^Citation28	Sharma^Citation29	Bharathi^Citation30	Sun^Citation31	Por^Citation32	Patel^Citation33
	2021	1993	1999	2008	2011	2012	2000	2007	2006	2009	2010
No. eyes	44	77	87	72	59	42	39	33	20	43	25
Culture/smear +ve	40%	64%	50%	74%	53	87	100	100	100	88	60
Mean age (y)	31	NR	33	29	34	34	37	NR^A	26	26	40
Mean time to Dx (d)	20	25	68	NR^B	39	11	NR^C	NR^D	42	29	41
Risk Factors
Contact lens wear	66%	89%	75%	89%	97	93	0	0	60	100	96
Prior topical steroid	25%	NR	35%	82%	69	62	NR	NR	NR	24	56
Clinical characteristics
Ring infiltrate	45.5%	49%	29%	19	32	60	41	45	30	29	32
Perineuritis	65.9%	41%	2%	22	17	38	3	NR	10	45	12
Epitheliopathy	43.2%	37%	NR	38	46	NR	0	0	25	NR	64
Pseudodendrites	43.2%	8%	NR	NR	NR	12	3	NR	NR	17	NR
Hypopyon	15.9%	26%	NR	NR	5	7	54	27	20	NR	20

Notes: NR^A: 33.3% were <40 years, 39.4% were 41–50 years, and 27.3% were >50 years. NR^B: 60.7% diagnosed >3 weeks after start of symptoms. NR^C: 38.5% diagnosed >30 days after start of symptoms. NR^D: 75.8% diagnosed >7 weeks after start of symptoms.

Abbreviation: NR, not reported (shaded cells).

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