Given the chance your cat may only have one kidney, I would think the worst case scenario would be kidney disease, which untreated can lead to possible renal failure.
1	Given	give	VERB	VBN	Tense=Past|VerbForm=Part	3	case	3:case	_
2	the	the	DET	DT	Definite=Def|PronType=Art	3	det	3:det	_
3	chance	chance	NOUN	NN	Number=Sing	14	obl	14:obl:given	_
4	your	your	PRON	PRP$	Case=Gen|Person=2|Poss=Yes|PronType=Prs	5	nmod:poss	5:nmod:poss	_
5	cat	cat	NOUN	NN	Number=Sing	8	nsubj	8:nsubj	_
6	may	may	AUX	MD	VerbForm=Fin	8	aux	8:aux	_
7	only	only	ADV	RB	_	8	advmod	8:advmod	_
8	have	have	VERB	VB	VerbForm=Inf	3	acl:relcl	3:acl:relcl	_
9	one	one	NUM	CD	NumForm=Word|NumType=Card	10	nummod	10:nummod	_
10	kidney	kidney	NOUN	NN	Number=Sing	8	obj	8:obj	SpaceAfter=No
11	,	,	PUNCT	,	_	14	punct	14:punct	_
12	I	I	PRON	PRP	Case=Nom|Number=Sing|Person=1|PronType=Prs	14	nsubj	14:nsubj	_
13	would	would	AUX	MD	VerbForm=Fin	14	aux	14:aux	_
14	think	think	VERB	VB	VerbForm=Inf	0	root	0:root	_
15	the	the	DET	DT	Definite=Def|PronType=Art	18	det	18:det	_
16	worst	bad	ADJ	JJS	Degree=Sup	17	amod	17:amod	_
17	case	case	NOUN	NN	Number=Sing	18	compound	18:compound	_
18	scenario	scenario	NOUN	NN	Number=Sing	22	nsubj	22:nsubj	_
19	would	would	AUX	MD	VerbForm=Fin	22	aux	22:aux	_
20	be	be	AUX	VB	VerbForm=Inf	22	cop	22:cop	_
21	kidney	kidney	NOUN	NN	Number=Sing	22	compound	22:compound	_
22	disease	disease	NOUN	NN	Number=Sing	14	ccomp	14:ccomp|27:nsubj	SpaceAfter=No
23	,	,	PUNCT	,	_	22	punct	22:punct	_
24	which	which	PRON	WDT	PronType=Rel	27	nsubj	22:ref	_
25	untreated	untreated	ADJ	JJ	Degree=Pos	27	advmod	27:advmod	_
26	can	can	AUX	MD	VerbForm=Fin	27	aux	27:aux	_
27	lead	lead	VERB	VB	VerbForm=Inf	22	acl:relcl	22:acl:relcl	_
28	to	to	ADP	IN	_	31	case	31:case	_
29	possible	possible	ADJ	JJ	Degree=Pos	31	amod	31:amod	_
30	renal	renal	ADJ	JJ	Degree=Pos	31	amod	31:amod	_
31	failure	failure	NOUN	NN	Number=Sing	27	obl	27:obl:to	SpaceAfter=No
32	.	.	PUNCT	.	_	14	punct	14:punct	_
