📞 219-931-5227 8840 Calumet Ave, Munster, IN 46321
Patient Portal 7 Locations
Northwest Indiana · Kidney Diseases & Hypertension

Specialized Kidney Care
Across Northwest Indiana

Nephrology Specialists, P.C. provides board-certified nephrology care at seven convenient locations — bringing expert management of chronic kidney disease, hypertension, and dialysis close to where you live.

Request an Appointment Find a Location
7
NW Indiana locations
7
Board-certified physicians
25+
Years serving NW Indiana
Nephrology specialist reviewing patient records
Contact Us
📞
Main Phone
219-931-5227
📍
Main Office
8840 Calumet Ave
Munster, IN 46321
🕐
Office Hours
Monday – Friday
8:00 AM – 5:00 PM
🏥
All Locations
Munster · Gary · Merrillville
Michigan City · Portage · Valparaiso · Whiting
🔐
Patient Portal
Labs & messaging
💳
Pay My Bill
Secure online payment
📅
Request Appointment
New & returning patients
📚
Patient Education
Kidney health guides
📍
Find a Location
7 offices in NW Indiana
What We Treat

Comprehensive Kidney Disease Care

Our nephrologists manage the full spectrum of kidney disease — from early CKD and hypertension to end-stage renal disease and transplant care.

🫘

Chronic Kidney Disease (CKD)

Comprehensive management of all CKD stages — slowing progression, monitoring GFR, and preparing patients for renal replacement therapy when needed.

💧

Dialysis Care

Hemodialysis and peritoneal dialysis coordination, vascular access management, and ongoing monitoring in partnership with regional dialysis centers.

❤️

Hypertension

Evaluation and management of resistant hypertension with particular attention to its impact on kidney function and cardiovascular risk.

🔬

Glomerular Disease

Diagnosis and treatment of nephritis, nephrotic syndrome, lupus nephritis, IgA nephropathy, and other immune-mediated kidney conditions.

⚡

Acute Kidney Injury

Rapid evaluation and management of AKI in hospital and outpatient settings, including identification of reversible causes and prevention of CKD progression.

🏥

Transplant Nephrology

Pre-transplant evaluation and post-transplant co-management in collaboration with regional transplant centers.

Nephrologist in consultation with patient
Personalized patient care
Physician explaining kidney anatomy model
Expert kidney disease management
Specialist reviewing patient lab results
Evidence-based diagnosis & treatment
Our Physicians

Meet Your Nephrology Team

All seven physicians are board-certified in Internal Medicine and Nephrology. Our physicians bring fellowship-trained expertise and a commitment to personalized, compassionate care.

Dr. Raied Abdullah
Dr. Raied Abdullah, M.D.
Nephrology & Internal Medicine
Board-certified nephrologist with expertise in chronic kidney disease management and hypertension.
View full bio →
Dr. Maher Ajam
Dr. Maher Ajam, M.D.
Nephrology & Internal Medicine
Board-certified nephrologist focused on CKD, dialysis care, and electrolyte disorders.
View full bio →
Dr. Shahabul Arfeen
Dr. Shahabul Arfeen, M.D., FACP, FRCP
FACP · FRCP (UK) · Nephrology
Fellow of the American College of Physicians and Royal College of Physicians (UK).
View full bio →
Dr. Sanjeev Rastogi
Dr. Sanjeev Rastogi, M.D., M.R.C.P.
MRCP · Nephrology
Member of the Royal College of Physicians with extensive nephrology and internal medicine expertise.
View full bio →
Dr. Mohammad Saleh
Dr. Mohammad Saleh, M.D.
Nephrology & Internal Medicine
Board-certified nephrologist treating the full spectrum of kidney and hypertension conditions.
View full bio →
Dr. Jonathan Silverman
Dr. Jonathan Silverman, M.D.
Nephrology & Internal Medicine
Board-certified nephrologist with a focus on patient-centered kidney care across NW Indiana.
View full bio →
Dr. Mohammad Tinawi
Dr. Mohammad Tinawi, M.D.
Nephrology & Internal Medicine
Board-certified nephrologist providing comprehensive kidney disease and hypertension care.
View full bio →
Physician explaining kidney anatomy
Patient education
Understanding your
kidney health

Plain-language guides to help you understand what's happening with your kidneys and what to expect from your care.

View all education topics →
💬
Not sure where to start?
If you've recently been told you have kidney disease or high blood pressure affecting your kidneys, it can feel overwhelming. Start with "Understanding CKD" below — then bring your questions to your next appointment. Your care team is here to explain everything in plain terms.
Most Common

Understanding Chronic Kidney Disease

What CKD means, how it's measured (GFR & stages), why it matters, and what you can do to slow its progression. This is the starting point for most of our patients.

Read more → CKD · Stages 1–5
Dialysis

Dialysis: Hemodialysis vs. Peritoneal

A straightforward comparison of your dialysis options — how each works, what a typical week looks like, and how to think about choosing what's right for you.

Read more → HD · PD · Access
Diet & Lifestyle

Eating Well with Kidney Disease

Managing potassium, phosphorus, sodium, and protein doesn't have to mean giving up food you enjoy. Practical guidance on a kidney-friendly diet.

Read more → Nutrition · CKD Diet
Blood Pressure

High Blood Pressure & Your Kidneys

Hypertension is both a cause and a consequence of kidney disease. Learn why BP control is critical and how we approach individualized treatment.

Read more → Hypertension · CKD
Transplant

Kidney Transplant: What to Expect

From evaluation and the waitlist to living donors and post-transplant monitoring — a clear overview of the transplant process and our role in your care.

Read more → Transplant · ESRD
Medications

Medications & Your Kidneys

Common over-the-counter drugs — including NSAIDs, antacids, and certain antibiotics — can harm kidney function. Know what to discuss with your team.

Read more → Nephrotoxins · Safety
Interactive tool

CKD Progression Calculator

Enter your serum creatinine, age, and sex to estimate your eGFR and CKD stage. The interactive stage slider walks through each stage showing symptoms, what to expect, and recommended actions — with direct links to our DaVita dialysis education resources.

6
CKD stages
2021
CKD-EPI
eGFR
+ risk
Open CKD Calculator →

Educational — not a substitute for medical advice

Where to Find Us

Seven Locations Across Northwest Indiana

We maintain offices throughout the region so specialist kidney care is accessible no matter where you live. Call our main number and we'll direct you to the closest location.

01
Munster
8840 Calumet Ave
Munster, IN 46321
Main Office
02
Gary
3503 Martin Luther King Dr
Gary, IN
03
Merrillville
521 E. 86th Ave
Merrillville, IN
04
Michigan City
9836 W. 400 N.
Michigan City, IN
05
Portage
5823 US Highway 6
Portage, IN
06
Valparaiso
606 E. Lincoln Way
Valparaiso, IN
07
Whiting
2075 Indianapolis Blvd
Whiting, IN

Questions about a location's hours? Call 219-931-5227

Insurance & Referrals

Accepted Insurance Plans

We participate with most major insurance plans. Verify your specific coverage with our billing team before your visit.

Aetna
Anthem
Blue Cross Blue Shield of IL
CareSource
Cigna
Humana
Illinois Medicaid
Indiana Medicare
Managed Health
MdWise
Multiplan PHCS
PHP
Railroad Medicare
Tricare / Humana Military
UnitedHealthcare
If your insurance is not listed, please call 219-931-5227. If we do not participate with your plan but your plan allows out-of-network benefits, our staff will assist you with the reimbursement paperwork.

Referring Physicians

We welcome referrals from primary care and specialist physicians across the region. Please include recent labs (BMP, CBC, urinalysis), reason for consultation, and patient demographics.

📠 219-931-5227

What to Bring to Your First Visit

Photo ID & insurance card · Recent lab results (BMP, urinalysis) · Medication list · Referral from your PCP (may be required by your plan) · Any prior imaging or biopsy reports

💳 Online Bill Pay

Pay Your Bill Online

We're setting up a dedicated, secure online payment portal so you can pay from any device without calling the office. A Stripe-powered payment page is in development — in the meantime, use the options on the right.

🔒
PCI-compliant card processing via Stripe
📧
Automatic payment confirmation by email
📱
Works on any phone, tablet, or computer
🧾
Visa, Mastercard, Discover, Amex & HSA/FSA accepted
Payment Options
🔧
New Payment Portal Coming Soon
We're finalizing our secure online payment system. You'll be able to pay directly from this page shortly.
Current options
Existing portal cds.care/billpay ↗
By phone 219-931-5227
In person Cash or check at any office
Get in Touch

Contact & Appointments

Use the form to request an appointment or send a general question. For urgent matters, please call us directly at 219-931-5227.

📞
Phone
219-931-5227
Mon – Fri, 8:00 AM – 5:00 PM
📍
Main Office
8840 Calumet Ave
Munster, IN 46321
🏥
All Locations
Munster · Gary · Merrillville
Michigan City · Portage
Valparaiso · Whiting
🔐
Patient Portal
Log In to Patient Portal ↗
View labs, visit notes & messages

Request an Appointment

We'll contact you within one business day to confirm. Urgent concerns? Call us directly.

New patients welcome · Referral may be required by your insurance plan