Main findings

1. Severe vitamin D deficiency
   • 25-OH vitamin D: 3.86 ng/mL
   • Deficiency is generally defined as below 20 ng/mL. This is markedly low.
   • It can contribute to bone or muscle pain, fatigue, weakness, cramps, low mood, and increased long-term bone-risk.
2. Early iron deficiency with mild anemia
   • Hemoglobin: 11.5 g/dL (low)
   • MCHC: 31.2 g/dL (slightly low)
   • RDW: 14.2% (slightly high)
   • Transferrin saturation: 11.88% (low)
   • Serum iron: 41.4 µg/dL, low-normal
   • This pattern fits iron-restricted red-cell production. A transferrin saturation below 15% is typical of iron deficiency. Symptom to Diagnosis, p. 9847; Quick Compendium of Clinical Pathology, p. 8074.

• Random glucose 86 mg/dL and HbA1c 5.6%: no diabetes by these results.
• Kidney filtration and creatinine: normal.
• Liver enzymes/proteins: normal.
• Thyroid profile: normal.
• Calcium: normal.
• CA-125: normal, but it is not a screening test that can by itself rule out ovarian disease.
• Total cholesterol/triglycerides: favorable. LDL 104 mg/dL is slightly above “optimal,” but not concerning in isolation at age 26.
• White-cell and platelet counts: normal.
• Blood pressure 123/86: systolic is normal; the diastolic value is borderline elevated if consistently present, so repeat measurements at rest are sensible.

Differential diagnosis

A. Mild anemia / iron deficiency pattern

1. Menstrual blood loss
   • Common cause in a 26-year-old woman, particularly with heavy periods, clots, bleeding beyond 7 days, or short cycles.
   • Consider fibroids, adenomyosis, endometriosis, or hormonal causes if periods are heavy or painful.
2. Low dietary iron intake
   • More likely with vegetarian/vegan eating patterns, low overall protein intake, restrictive dieting, or low intake of iron-rich foods.
3. Reduced iron absorption
   • Celiac disease, H. pylori gastritis, inflammatory bowel disease, prior bariatric surgery, chronic diarrhea, or acid-suppressing medicines can reduce absorption.
4. Early iron deficiency before marked microcytosis
   • The MCV is still normal at 86.6 fL. Iron deficiency can be present before red cells become classically small.

• More relevant with black stools, persistent abdominal pain, change in bowel habits, unexplained weight loss, family history of bowel cancer, regular NSAID use, or no heavy menstrual bleeding.

1. Anemia of chronic inflammation
   • Can lower serum iron and saturation, but is less supported here because there is no strong inflammatory signal and TIBC is not low. Ferritin and clinical context distinguish this from true iron deficiency.
2. Vitamin B12-related anemia
   • B12 is low-normal/borderline at 217 pg/mL, but the normal MCV makes B12 deficiency a less likely explanation for the current anemia. It could coexist, especially if there is tingling, numbness, mouth ulcers, memory/concentration difficulty, or a restrictive diet.

• Serum ferritin, ideally with CRP if inflammation is suspected.
• Repeat CBC and iron profile after treatment.
• Menstrual history and dietary review.
• If periods are not heavy or there are gastrointestinal symptoms: discuss celiac screening, H. pylori testing, and targeted GI evaluation with a clinician.
• Consider B12 confirmation with methylmalonic acid or homocysteine if symptoms or risk factors exist.

B. Severe vitamin D deficiency

1. Low sunlight exposure
   • Indoor work/study, sun avoidance, covered clothing, and limited mid-day exposure are common causes.
2. Low dietary vitamin D intake
   • Few foods naturally provide sufficient vitamin D without fortified foods or supplements.
3. Higher body weight or reduced bioavailability
   • Vitamin D can be less bioavailable with higher adiposity.
4. Skin pigmentation or sunscreen use
   • Darker skin produces less vitamin D in the same sunlight conditions.

• Celiac disease, inflammatory bowel disease, pancreatic disease, cholestatic liver disease, or prior bariatric surgery.

1. Medication-related reduction
   • Some antiepileptic drugs, glucocorticoids, rifampicin, and certain other medicines can lower vitamin D.
2. Kidney/liver disease
   • Less likely in this report because kidney function, liver enzymes, albumin, and calcium are normal.

What to do

• Book a non-urgent appointment with a primary-care doctor or gynecologist within the next few weeks to confirm the cause and prescribe a replacement plan for vitamin D and iron if appropriate.
• Ask specifically for ferritin. It is the key missing test to establish iron-store depletion.
• Do not assume that all tiredness, hair loss, breathlessness, palpitations, or body aches are solely due to these results. Symptoms and examination matter.
• A clinician may prescribe a higher-dose vitamin-D repletion course followed by maintenance, then recheck 25-OH vitamin D and calcium. Do not self-start prolonged high-dose vitamin D without advice.
• Iron treatment should be paired with identifying the reason for iron depletion, especially menstrual loss versus dietary or absorption causes.

Seek prompt medical assessment if you have

• Fainting, chest pain, severe shortness of breath, fast persistent heartbeat, or worsening dizziness.
• Black/tarry stool, blood in stool, vomiting blood, or severe abdominal pain.
• Very heavy menstrual bleeding, such as soaking pads/tampons hourly, passing large clots, or bleeding with dizziness.
• New numbness, tingling, gait imbalance, or marked weakness, particularly given the borderline B12 result.

• Creatinine: 0.61 mg/dL - normal for an adult woman.
• eGFR: 126 mL/min/1.73 m² - normal filtration.
• Urea: 11.41 mg/dL and BUN: 5.33 mg/dL - mildly low.
• The low urea/creatinine and BUN/creatinine ratios simply reflect the low urea/BUN. They do not independently diagnose kidney disease.

Why BUN and urea may be low

1. Low recent protein intake
   • Low intake of pulses, dairy, eggs, meat/fish, soy, or overall calories.
   • This is particularly plausible given your iron-deficiency pattern and very low vitamin D, which may point toward nutritional gaps.
2. High fluid intake before the blood draw
   • Drinking a lot of water can dilute BUN and urea temporarily.
3. Small body size or relatively low muscle mass
   • Creatinine comes mainly from muscle metabolism. Women commonly have lower creatinine than men, and a value of 0.61 is normal for you.
4. Pregnancy
   • If applicable, increased blood volume can lower both BUN and creatinine.
5. Liver disease or severe malnutrition
   • These can reduce urea production, but are unlikely here: your bilirubin, AST, ALT, alkaline phosphatase, albumin, and total protein are normal. Low BUN may occur with low protein intake, malnutrition, or liver disease, as described in MedlinePlus guidance. Goldman-Cecil Medicine, p. 2645 also notes a low BUN/creatinine ratio with poor protein intake, malnutrition, or liver disease.

Does the low creatinine need concern?

What you should do

• Ensure adequate overall nutrition and protein intake, especially while correcting the iron and vitamin-D deficiencies.
• There is no need to “treat” a low BUN alone.
• Repeat kidney tests only as part of routine follow-up or if your clinician advises it.
• Seek assessment if you have unintentional weight loss, chronic diarrhea, poor appetite, swelling, jaundice, persistent vomiting, or known liver disease.

Differential count interpretation

What it means

1. Mild relative lymphocytosis

• Normal biological variation
• Recent or resolving viral infection, including a mild cold that may have caused few or no symptoms
• Recovery phase after an infection
• Stress, sleep disruption, or transient immune variation

2. Mild relative reduction in neutrophil percentage

3. Slightly high monocyte percentage

Overall picture

• No leukopenia
• No clinically significant neutropenia
• No absolute lymphocytosis
• No eosinophilia suggesting a strong allergic/parasitic pattern
• No platelet abnormality
• No blood-count pattern suggestive of leukemia or serious bone marrow disease

When to repeat or investigate

• Recurrent or unusual infections, persistent fever, mouth ulcers
• Enlarged lymph nodes, night sweats, unintentional weight loss
• Persistently worsening fatigue, breathlessness, or palpitations
• A future ANC below 1,500/µL or rising absolute lymphocyte count