SQL Server 2019

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AccountNo	RunKey	RunDate	Item	Value	PreValue	PreDate
12345	4	2017-06-22	PromotionDate	2017-06-21	2017-01-15	2017-06-21
12345	4	2017-06-22	Salary	65000	60000	2017-06-21

Declare @YourTable Table ([AccountNo] int,[RunKey] int,[RunDate] date,[Address] varchar(50),[Salary] int,[PromotionDate] date)
Insert Into @YourTable Values 
 (12345,2,'06/20/2017','123 Main Street',60000,'01/15/2017')
,(12345,3,'06/21/2017','123 Main Street',60000,'01/15/2017')
,(12345,4,'06/22/2017','123 Main Street',65000,'06/21/2017');

with ct as
(
select  A.AccountNo
       ,A.RunKey
       ,A.RunDate
       ,B.Item
       ,B.Value
from   @YourTable A
cross apply (values  ('Address'      ,cast(A.[Address] as varchar(max)))
                    ,('Salary'       ,cast(A.[Salary]  as varchar(max)))
                    ,('PromotionDate',cast(A.[PromotionDate] as varchar(max)))
                 ) B (Item,Value)
)
select  a.AccountNo
       ,a.RunKey
       ,a.RunDate
       ,stuff ((select (',' + Item) from ct b 
                where b.AccountNo=a.AccountNo 
                      and b.RunKey=a.RunKey 
                      and b.RunDate=a.RunDate
                      for xml path(''), type ).value('.', 'nvarchar(MAX)'),1,1,'') Item
        ,stuff ((select (',' + Value) from ct b 
                where b.AccountNo=a.AccountNo 
                      and b.RunKey=a.RunKey 
                      and b.RunDate=a.RunDate
                      for xml path(''), type ).value('.', 'nvarchar(MAX)'),1,1,'') Value
from   ct a
group by a.AccountNo, a.RunKey, a.RunDate

AccountNo	RunKey	RunDate	Item	Value
12345	2	2017-06-20	Address,Salary,PromotionDate	123 Main Street,60000,2017-01-15
12345	3	2017-06-21	Address,Salary,PromotionDate	123 Main Street,60000,2017-01-15
12345	4	2017-06-22	Address,Salary,PromotionDate	123 Main Street,65000,2017-06-21