Clear my Doubts

It's sorta agent commission principle relationship. 

Path lab will debit bank and credit sales

Eg

Bank Dr. 42

Sales cr. 42

And the rest is transferred to lab. If you want to record it then

Bank Dr. 100

Sales cr. 42

Bank Cr. 58

When a path lab running on a franchise basis collects Rs. 100 from a patient and gives the main lab Rs. 58 for the test, the following entry will be passed:

Cash/Bank A/c/Accounts receivable Dr. Rs.100

          To Franchise Commission Received A/c Rs.42

           To Main Lab A/c Rs.58

Accounts receivables? Ok your fine here. But in general accounting terms it's creditors or payables. Indas rule! In reporting we don't put up creditors and debtors names.