| Irregularly contracted cells | Blood | Hematology and Cell counts | LP393414-0 | 1 |
| Isocitrate | LP18440-5 | 1 |
| Isocitrate | Urine | Chemistry - non-challenge | LP386202-8 | 1 |
| Isocoproporphyrin | LP30895-4 | 1 |
| Isocoproporphyrin | Stool | Chemistry - non-challenge | LP386476-8 | 1 |
| Isoheptacarboxylporphyrin | LP14339-3 | 1 |
| Isoheptacarboxylporphyrin | Stool | Chemistry - non-challenge | LP386477-6 | 1 |
| Isohexacarboxylporphyrin | LP14340-1 | 1 |
| Isohexacarboxylporphyrin | Stool | Chemistry - non-challenge | LP386478-4 | 1 |
| Isoleucine | Amniotic fluid | Chemistry - non-challenge | LP384069-3 | 1 |
| Isoleucine | Cerebral spinal fluid | Chemistry - non-challenge | LP384072-7 | 1 |
| Isoleucine | DBS | Chemistry - non-challenge | LP384070-1 | 1 |
| Isopentacarboxylporphyrin | LP14341-9 | 1 |
| Isopentacarboxylporphyrin | Stool | Chemistry - non-challenge | LP386479-2 | 1 |
| Isopropanol | LP14375-7 | 1 |
| Isopropanol | Serum or Plasma | Drug toxicology | LP387477-5 | 1 |
| Isospora belli | LP14900-2 | 1 |
| Isospora belli | XXX | Microbiology | LP376786-2 | 1 |
| Isovalerylcarnitine (C5) | LP19306-7 | 1 |
| Isovalerylcarnitine (C5) | Serum or Plasma | Chemistry - non-challenge | LP381617-2 | 1 |
| Isovalerylcarnitine+Methylbutyrylcarnitine (C5) | Serum or Plasma | Chemistry - non-challenge | LP381614-9 | 1 |
| Isoxanthopterin | LP200430-9 | 1 |
| Isoxanthopterin | Serum or Plasma | Chemistry - non-challenge | LP384308-5 | 1 |
| JAK2 gene | LP36473-4 | 1 |
| JAK2 gene p.Val617Phe | LP36477-5 | 1 |
| JAK2 gene p.Val617Phe | Blood or Tissue | Mutations | LP409885-3 | 1 |
| Kappa light chains | Serum | Chemistry - non-challenge | LP384878-7 | 1 |
| Kappa light chains | Serum or Plasma | Chemistry - non-challenge | LP384879-5 | 1 |
| Karyotype | Amniotic fluid | Molecular pathology | LP401853-9 | 1 |
| Karyotype | Blood or Tissue | Molecular pathology | LP401854-7 | 1 |
| Karyotype | Bone marrow | Molecular pathology | LP401856-2 | 1 |
| Keratan sulfate | DBS | Chemistry - non-challenge | LP386015-4 | 1 |
| Keratan sulfate | Serum or Plasma | Chemistry - non-challenge | LP412142-4 | 1 |
| Keratan sulfate | Urine | Chemistry - non-challenge | LP386016-2 | 1 |
| Ketones | Serum or Plasma | Chemistry - non-challenge | LP386314-1 | 1 |
| Kidney failure 2-year risk | LP248942-7 | 1 |
| Kidney failure 2-year risk | Patient | Chemistry - non-challenge | LP386663-1 | 1 |
| Kidney failure 5-year risk | LP248943-5 | 1 |
| Kidney failure 5-year risk | Patient | Chemistry - non-challenge | LP386664-9 | 1 |
| Krabbe disease | LP113917-1 | 1 |
| Krabbe disease | DBS | Chemistry - non-challenge | LP421932-7 | 1 |
| Kynurenin | LP70439-2 | 1 |
| Kynurenin | Serum or Plasma | Chemistry - non-challenge | LP384405-9 | 1 |
| L-2-hydroxyglutarate | Amniotic fluid | Chemistry - non-challenge | LP386253-1 | 1 |
| L-2-hydroxyglutarate | Cerebral spinal fluid | Chemistry - non-challenge | LP386255-6 | 1 |
| L-2-hydroxyglutarate | DBS | Chemistry - non-challenge | LP386254-9 | 1 |
| L-2-hydroxyglutarate | Serum or Plasma | Chemistry - non-challenge | LP386256-4 | 1 |
| L-serine | Cerebral spinal fluid | Chemistry - non-challenge | LP384347-3 | 1 |
| L-serine | Serum or Plasma | Chemistry - non-challenge | LP384348-1 | 1 |
| Lacosamide | LP100041-5 | 1 |
| Lacosamide | Serum or Plasma | Drug toxicology | LP390789-8 | 1 |
| Lactase | LP207986-3 | 1 |
| Lactase | Small intestine Tissue | Chemistry - non-challenge | LP383123-9 | 1 |
| Lactate | Blood arterial | Chemistry - non-challenge | LP385562-6 | 1 |
| Lactate | Urine | Chemistry - non-challenge | LP385578-2 | 1 |
| Lactate dehydrogenase 1 | LP15688-2 | 1 |
| Lactate dehydrogenase 1 | Serum or Plasma | Chemistry - non-challenge | LP383089-2 | 1 |
| Lactate dehydrogenase 2 | LP15689-0 | 1 |
| Lactate dehydrogenase 2 | Serum or Plasma | Chemistry - non-challenge | LP383096-7 | 1 |
| Lactate dehydrogenase 3 | LP15690-8 | 1 |
| Lactate dehydrogenase 3 | Serum or Plasma | Chemistry - non-challenge | LP383102-3 | 1 |
| Lactate dehydrogenase 4 | LP15691-6 | 1 |
| Lactate dehydrogenase 4 | Serum or Plasma | Chemistry - non-challenge | LP383108-0 | 1 |
| Lactate dehydrogenase 5 | LP15692-4 | 1 |
| Lactate dehydrogenase 5 | Serum or Plasma | Chemistry - non-challenge | LP383114-8 | 1 |
| Lactoferrin | LP15694-0 | 1 |
| Lactoferrin | Stool | Chemistry - non-challenge | LP384768-0 | 1 |
| Lactose | LP15269-1 | 1 |
| Lactose | Urine | Chemistry - non-challenge | LP385588-1 | 1 |
| Lambda light chains | Serum or Plasma | Chemistry - non-challenge | LP384894-4 | 1 |
| Lambda light chains.free | Serum | Chemistry - non-challenge | LP384897-7 | 1 |
| Lambda light chains.free | Serum or Plasma | Chemistry - non-challenge | LP384898-5 | 1 |
| Lamellar bodies | LP18987-5 | 1 |
| Lamellar bodies | Amniotic fluid | Hematology and Cell counts | LP393487-6 | 1 |
| lamoTRIgine | LP17251-7 | 1 |
| lamoTRIgine | Serum or Plasma | Drug toxicology | LP390792-2 | 1 |
| Lanosterol | LP173718-0 | 1 |
| Lanosterol | Serum or Plasma | Chemistry - non-challenge | LP382494-5 | 1 |
| Laurate (C12:0) | Red Blood Cells | Chemistry - non-challenge | LP382067-9 | 1 |
| Laurate (C12:0) | Serum or Plasma | Chemistry - non-challenge | LP382068-7 | 1 |
| Lauroleate (C12:1) | Red Blood Cells | Chemistry - non-challenge | LP382086-9 | 1 |
| Lauroleate (C12:1) | Serum or Plasma | Chemistry - non-challenge | LP382087-7 | 1 |
| LDL 1 | LP36474-2 | 1 |
| LDL 1 | Serum or Plasma | Chemistry - non-challenge | LP382571-0 | 1 |
| LDL 2 | LP56924-1 | 1 |
| LDL 2 | Serum or Plasma | Chemistry - non-challenge | LP382572-8 | 1 |
| LDL 3 | LP56925-8 | 1 |
| LDL 3 | Serum or Plasma | Chemistry - non-challenge | LP382573-6 | 1 |
| LDL 4 | LP36475-9 | 1 |
| LDL 4 | Serum or Plasma | Chemistry - non-challenge | LP382574-4 | 1 |
| Lead | Blood | Drug toxicology | LP388318-0 | 1 |
| Lead | Blood venous | Drug toxicology | LP388320-6 | 1 |
| Lead | Serum or Plasma | Drug toxicology | LP388329-7 | 1 |
| Leflunomide | LP34970-1 | 1 |
| Leflunomide | Serum or Plasma | Drug toxicology | LP388688-6 | 1 |
| Legionella sp | LP16652-7 | 1 |
| Legionella sp | XXX | Microbiology | LP444510-4 | 1 |
| Leptin | LP19488-3 | 1 |
| Leptin | Serum or Plasma | Chemistry - non-challenge | LP381326-0 | 1 |
| Leucine | Amniotic fluid | Chemistry - non-challenge | LP384097-4 | 1 |