Diagnosis is usually made on the basis of history and physical examination alone. Only in the presence of specific suspected diagnoses (such as tumor diseases or infections) is laboratory diagnostics necessary.
If warning signs (“red flags”) are present, further imaging or laboratory tests and/or referral to specialist care should be initiated depending on the suspected diagnosis and urgency.
2nd order laboratory parameters – depending on the results of the history, physical examination, etc. – for differential diagnostic clarification.
- Small blood count
- Inflammatory parameters – CRP (C-reactive protein) or ESR (erythrocyte sedimentation rate).
- Urine examination – test strips, urine sediment, urine culture (bacteriology: pathogen, resistogram).
- Alkaline phosphatase (AP) isoenzymes, ostase, urinary calcium (tumor hypercalcemia (synonym: tumor-induced hypercalcemia (calcium excess), TIH) is one of the most common symptoms in paraneoplastic syndromes), PTHrP (parathyroid hormone-related protein; the constellation with decreased parathyroid hormone (PTH) and increased PTHrP is typical for tumor hypercalcemia) – if bone metastases are suspected.
- Deoxypyridinoline (DPD) – is > 98% bone specific – a good index of bone resorption rate (elevated in: peri- and postmenopausal osteoporosis (early detection possible with still normal bone densitometry); bone metastases; plasmocytoma (multiple myeloma); Paget’s disease; primary hyperparathyroidism (parathyroid hyperfunction).
- Tumor markers: CEA (carcinoembryonic antigen), TPA (tissue polypeptide antigen); PSA (prostate-specific antigen).
- Serum electrophoresis – if multiple myeloma (plasmocytoma) is suspected.
